To answer your questions, YES, the link wheel still works, but only if you do it right, I mean, it all depends on the quality of your link wheels.

A properly built link wheel, will take more time (and/or money) to build but the results will be up there, you'll get increased keyword rankings and also indirect traffic from the link wheel sites, and contrary to popular belief, if you build it right, google will not be able to spot it and you'll be penalty free.

If you plan to build a link wheel, I would recommend you to read all the resources at linkwheel.pro before you start building one.

To answer your question, YES, it has high trust and high authority so a link from that site would definitely help in terms of SEO.

Even if your site outranks the other site in Moz, it doesn't mean anything. Moz is not Google, they have different ranking signals (have a second read at what Bob said) and the most important thing, Moz doesn't show all the links websites have, it shows only the links it found. This being the case, Google is probably aware of more links (hidden ones as well), so that's why your website is outranked.

It's exactly how Christina put it:

• keyword in title (the more keywords in title the better)

• title needs to make sense (as a sentence, not just as an enumeration of keywords)

• keyword closer to the beginning of the title it's a common practice

• keep it up to 70 characters long (google will truncate longer titles)

• also use your brand / site name somewhere

The example Christina gave is great, but to include even more keywords (and if you company is a local one) I would do:

"Top Rated UK Web Design Company - DR Adept" - as this would include the keywords uk web design company, top rated web design company, etc (combinations of all the words in there, you get the drift) - it won't rank as well for all of them, but it will be there.

Check with ahrefs or majestic, check the links manually or using a tool like link detox and then you'll know what needs to be done.

There will be only a single benefit, which is tracking. Separate subdomains will allow you track visitors properly. No positive or negative result - unless links are involved.

The only way to go is up, just make sure you keep your titles well optimized.

I think it has something to do with keyword match types (it's the same thing as with google adwords) - http://advertise.bingads.microsoft.com/en-us/help-topic/how-to/50822/what-are-keyword-match-types-and-how-do-i-use-them

The pagerank won't update. What you have now is what you'll have (probably forever). Good thing is that pagerank doesn't count. Your low DA/PA is due to the few links or low quality links you may have. If you want to increase it, you'll need more links (from high PA pages of course).