I have had an account at SEMrush for a long time and they have a long history of what I track.

I track "baskets" of keywords.

Let's say I am running a website about hammers and I want to rank #1 for the root keyword of "hammers".  Early in the planning of this business and its website I do keyword research and determine that I will be selling hammers made by different companies (with a number of models from each company), hammers used by different occupations (and numerous hammers for some occupations)... I will also have lots of articles about hammers that include: how to select them, how to use them, how to avoid injuries, care of your hammer, etc.

So I am going to go for the root keyword of "hammers" (which might take several years to accomplish - but I am the hammer man and I plan to hammer at this until everyone else drops dead).

Then starts my baskets, each will be a keyword "project" at SEMrush.  These keyword projects will each have many keywords tracked.  We might have a few dozen projects running for this website.  These will track website performance for different parts of the attack.  Knowing where you are succeeding, where traction is hard to get, where you are making money, etc.

BRANDS:  Estwing (and a keyword for each type of hammer, perhaps weight as well, or length), then Black and Decker,  Kobalt, Irwin, Vaughan, etc.

HAMMERS by OCCUPATION:  carpenter, mason, auto body,  etc.

**ARTICLES: ** how to select, how to use, types of handles (wood, drop forged, fiberglass), how to care for, safety (each of these will have several articles)

REVIEWS:  field tests of many types of hammers

RELATED PRODUCTS: that can be sold beside hammers

OTHERS: that will be discovered as the project progresses

Now we start a  content attack and a battle that will advance across time, tracking keywords on all of these levels, using sales data and profit margins as we learn them to prioritize the attack.

Your website might be smaller.  Your content attack might be simpler.  Your industry or business might have broad or narrow product lines and content opportunities.

So the number of keywords tracked might be dozens, hundreds or thousands.  You might have a nascent site and be tracking long tail easy, or you might have a mature site and be tracking mainly single-word root keywords.

I track a lot of keywords.  But each day I mainly look at the progress of the baskets, looking at individual keywords occasionally, but focusing on the big picture.    I load the baskets at the start of the project, knowing that I might not get to writing for some of those keywords for weeks, months or years - depending upon the size of the project.   As the project advances and I populate the keywords and the baskets, things start moving up, up, up.  That is what energizes me and keeps me on the attack.  A person's mental state is worth a million dollars.  The taste of blood and money is worth even more.   It helps keep me motivated and keeps me hammering hard.

I can see cases for using the .edu domain.

If you are in the business of educating people at your facility, at their facility, or on a website  then I would definitely start using the .edu domain.

If you are a publisher of academic content that is really good content and recommended by professors and used by students then I would use the .edu domain.

There are many domains that clearly communicate the business of the organization.   They bring "credibility even if undeserved"... and if you really deserve it then the .edu domain could be like throwing gasoline onto a fire in terms of attracting natural links and pulling clicks in the SERPs.

Which domain would you click (or type in) if you were looking for an educational organization named "wilson"?   Which one would you be more inclined to link to?

Wilson.com or Wilson.edu

There are .edu domains being used by organizations that are in the business of education, but most of their activities would be considered to be something other than students and teaching.  Smithsonian.edu, Getty.edu, GIA.edu.

Have you ever sent a link request to a website suggesting that they link to the most valuable page in the internet for a topic and they write back.... Wow!  That's a fantastic article, but we don't link to commercial websites?

If you have a website on wilson.com and send a link recommendation to loc.gov or nasa.gov, what are your chances of getting a link?   Does that change if your website is on wilson.edu?

You can find lots more discussion of pdf optimization here.

I forgot to address the tracking question...  We used to get server logs and run them through WeblogExpert.  You can set it up to track pdf impressions.

We don't do that any more because we turned off server logs because we felt it might take us out of GDPR compliance.

PDFs can pull in tons of traffic if they have high quality content.  I agree with allowing Google to index them.

PDFs can be optimized by editing their properties.  Editing the document title in properties has the optimization power of a <title>tag.</p> <p>It is probably worth the effort to look at the PDFs and plan how you can use them to drive traffic (through links) to relevant pages of your website.  Then if the PDFs get links, some of that power will pass through to the rest of your site. Breadcrumbs in PDFs will weave them into your website architecture.</p> <p>You can also sell ad space in the PDFs or place your own ads in there.  You can also place "buy buttons" in PDFs. </p> <p>There are lots of things that can be done with PDFs that most people have not thought of. </p></title>

All of the content that you have on a subdomain and all of the links that the subdomain attracts could have been working to strengthen your root domain.

In Google you are going out to fight the heavyweights.  Do you want to do that with a couple light weight platforms or do you want to unite the clans and attack with all that you got.   That is the choice that you make by running subdomains.

I moved and redirected my subdomains into folders on the main website a long time ago and the results were great.

I think that there is a good chance for an increase of total sales by combining the sites.  I vote for this because the two sites have diverse link profiles and combining them will make a big gain in the link diversity and domain authority of the site that remains.  I would merge them with optimism rather than with fear.

Google is probably not going to take any manual action based upon your complaint.   Keyword stuffing and hidden keywords have been around since the beginning of Google and they have algorithms that look for it.  These algorithms sometimes find it, sometimes don't find it, sometimes demote it and sometimes don't demote it.

I would not spend time trying to report this type of action.  I would spend that time instead working on my website.

For me, there are two issues.

A) If one of the variants is incorrect or ignorant then my visitors will see it.  This is a concern of people who run formal or academic sites. Some people might not link to me If I don't know how to spell some of the most commonly used words on my site.

B) Incorrect or ignorant usage could be a slight deduction from Google.

I usually go to Google.com and do a few searches.  That usually reveals what variants of the query are being used by people in their content and how Google will respond to the different variants.

In the case of "woodscrews"... Google says....

**About 3,990,000 results (0.54 seconds) **

Did you mean: wood screws

Now, I know what most vendors are using and see that Google will offer "wood screws" as the preferred variant.   So, I would write all of my content using that variant.   I usually agree with Google's preferred variant from my personal experience.  However, if their preferred variant was an incorrect usage or an ignorant usage, then I will think about how that would fit into my website.  But, since my websites are written in a formal context, I almost always go with proper, formal language.

Converting four categories of a blog into four outhouses will diminish your impact.

Keep those four categories on your current site and work to make then excellent.

You use two words that worry me... "growing" and "millions".    A ton of gold is worth a lot.  A ton of crap will sink a ship.

So, if your emphasis is on volume rather than quality, they you need a change of focus.

Hello Kingalan1,

If you are getting a nice increase in the number of people getting in touch for this time of year then you have made impressive improvements in the function and visitor satisfaction of the site.  Nice work.

I expect that you will see some kind of rankings increase.

First, nice work on getting a new website with metrics that might be better.

Since you only have a few days of data, and its over the Christmas holiday, don't bet on the new metrics yet.  They might simply be a result of return visitors stumbling around the site trying to find things that they were returning to see, or snooping around for something different.  Your metrics will probably be improved, but don't take it to the bank yet.

If you get improved metrics, will it increase your rankings?  In my opinion, it will depend more on how those metrics were obtained more than the metrics themselves.  If your new metrics are a result of people being more pleased with your site and that is what caused them to explore more then you might get a rankings increase.  If the new metrics are a result of it being more difficult for people to find they want then you might get a rankings decrease.

Will it change moz authority?  I don't know the answer to that question, and I would not give it a single wit of thought.  Why?  Moz authority has nothing to do with how Google ranks your website, how much money you are going to make, and what people think of your website.