I've got good news and bad news for you. And I'll start with the good: we are in the midst of a golden age of cameras, from every tier from entry-level to the enthusiast models you are looking at to the top of the line medium format options. There are hundreds of options which easily get an "excellent" rating in all the categories you describe. And you don't have to take my word for it; from a blog post Mike Johnston at The Online Photographer on the topic of mirrorless choice, here is a quote from photographer Ken Tanaka:

The simple fact is that one's choice of camera among this ever-widening belt of high-end "mirrorless" models from Fujifilm, Sony, and Olympus will have little impact of one's photographic results. We're in a hailstorm of outstanding products.

The choice of DSLR vs. mirrorless is similarly rosy: both options are great. DSLRs may be dinosaurs, but they're highly refined and close to the peak of their evolution — that meteor hasn't struck yet.

So, the good news is you really can't go wrong.

The bad news is that this doesn't help you make a choice, and unless you want to burn through a lot of cash and primarily be a gadget tester rather than a photographer, you do need to choose eventually. You're right that lens lineup is a reasonable way to narrow this down, as well as other aspects of the system as a whole. But, really, don't get too hung up there either — you're right to distrust Snapsort's valuation of factors like "number of lenses". To call out a particular example that you mentioned, there aren't a ton of Fujifilm X lenses, but the ones that exist are excellent, and Fujifilm has demonstrated a commitment to thoughtfully growing the lineup. My advice here is to consider the future, but don't get too hung up on it. Consider whether the system has the lenses to suit your basic wants now, and a few objects of desire in possible other directions, and don't agonize much more than that — buy into the system that is speaking to your heart. (And if it's truly a tie, flip a coin, or decide on price. Remember the good news — you can't go wrong.) The best camera is the one that gets you done worrying about what camera to buy and out shooting the fastest.

I also have some unsolicited advice... You mention a budget of $3000, and are looking at camera bodies that cost roughly half to two thirds of that. That's not a bad initial point, but if you are starting from scratch, you will probably be happier if you plan for a somewhat bigger outlay over the first year or so. It's not just the body and lenses — lighting is key to photography, and that means strobes and stands and modifiers. And almost everyone should at own at least a decent tripod. And you'll need memory cards and backpacks and all sorts of miscellany. Books. Possibly software. This all adds up. And that's not even considering that $1000 to $1500 probably isn't going to complete your basic working set of lenses. (If you think it will, you might want to consider whether this is really the camera body tier you want to be buying. You might get better results by spending less on the body and more on the rest. Or you might just spend less overall and still get results you are happy with.)