Website usability testing checklist in 2018

I've been pondering a lot recently about my method. Experience is a potent point, but it is rare that we try to map out that which we know and sit down.
Despite the fact that it is part of my compensated choices of one, I've decided to share this checklist. Several disclaimers: First, I actually don't claim this listing is special or extensive. Jakob Nielsen has a fantastic 113-point checklist in his e-book, Homepage Usability, for instance. This is just my way of organizing what I feel is essential while trying to keep it manageable. My usage of terms might differ from yours. I use "usability" in a very broad sense, and my use of "accessibility" isn't very industry standard. Don't like it? Write your own checklist ;) Ultimately, an advance warning this post is quite lengthy.
Basic Overview
The listing is split into 4 approximately equal sections, (I) Accessibility, (II) Id, (I-II) Navigation, and (IV) Content. I'll rationalize and describe all of line items and the sections under, but you can download the checklist as a basic, 1-page PDF.
I try to keep it easy with 3 basic scores: (1) Green Check = Good/Pass, (2) Red Check = Needs work, but no disaster, (3) Red X = Negative/Fail. Not all points are fundamentally applicable to all sites.

The Purpose Clear of tagline Makes Company's

Answer "What do you do?" concisely using a descriptive tag-line. Avoid advertising boil your distinctive worth proposition down to several words and jargon. This can be also an advantage for Search Engine Optimization.

Site H As Custom Perhaps Not-discovered/404 Page

In case a page in your site does not exist, a white page with "4 4 Perhaps Not Found" is a a great way to way to lose a customer. Create a custom 404 page, ideally one that guides your visitors to content.

Critical Content Is Above The Fold

The "fold" is that imaginary line where the bottom of your display cuts off a page. Content can fall below the fold, but such a thing critical to comprehending who you are or what you do (particularly on the home page) should fit on that first display. Average screen-resolution these days is depending on your audience.

HTML Titles On Pages Are Explanatory

More importantly, your page titles (in the tag) should be descriptive, unique, and not jammed total of keywords. Page titles are the first thing search-engine visitors see, and if those titles do not make feeling or look spammy, they will transfer on to the next result.