I'd only seriously consider VGF or RIV given their current pricing and long contracts. Financially, they are the 2 resorts that make sense. (Though I personally think it's silly to try to calculate the long term finances down to certainty, both RIV and VGF will almost certainly give far better value direct than any other WDW
DVC bought under current direct pricing).
From there, it's subjective. First and foremost, do you prefer being near MK/monorail or DHS/Epcot/Skyliner. A close second question, just which resort vibe do you like more. And perhaps 3rd, is there something about room choices that works or doesn't work for you.
My own subjective answers:
When my kids were young, we preferred the MK area. But now, we really prefer both DHS and Epcot. And we love the skyliner 90% of the time. So location-- Riviera wins for us.
2-- Personally, I prefer the look and feel of Riviera. The resort and rooms have a "casual elegance vibe" that we like. I really like that it's a pretty compact resort, always easy to get from point A to point B. No long walks to the pool or dining. The pools are really big for such a smallish resort.
3 -- room types -- probably not a factor. Nice to have the Tower Studios at RIV, but not sure we will ever use them. I do worry a little about whether the addition of so many studios at GFV will make it very hard to get the 1 and 2 BR units.
So subjectively, for me, RIV wins. But I don't think you can really go wrong picking between GFV and RIV. All the other resorts can be wonderful too, but the "sold out" pricing at those resorts make them less of a value. And the 2042 resorts are a straight rip-off to buy direct.