This is probably going to be a pretty large thread, so I won't be responding to everything, but there is a few things I want to touch on that I won't end up covering in eventual character-specific discussions.
The most common complaint we've seen about matchmaking is seeing the same people over and over. The reason people at the top can see people way below them is if it was something like only seeing people within 1000 points of them, some of them would literally only see 1 other person, or in the case of ranks 3-10 of this writing only seeing 10-20 people (and if that's all you see and are consistently winning... you'll be pushing a lot of what you see below you, seeing even less people).
It's annoying, but it's largely a product of this being in beta and there being a limited pool of our playerbase having access to PVP. Once we have the full player base at it this'll be a bit more constrained, but there's not much we can do about that with a limited player pool, sadly.
Basically the same answer as above; even though most people aren't attacking 100+ people a day, it'd start discouraging people from playing as they either only start matchmaking people way above them (punishing and asking for a loss) or matchmaking people way below them (basically bullying people who are weaker/not engaging as much).
(There's still the subject of the game encouraging people to revenge more than we expected people would; that's still on our radar as something to better constrain/discourage.)
The points do scale based on how different your points are from your opponent already; if you can get 24 points against him, he's certainly getting less than the baseline 19 points from beating you. The reason the scaling isn't more aggressive is it would otherwise make it near impossible for people who more consistently win and climb higher to not immediately lose all that progress (since they have far fewer/no people with similar or better points than them). Obviously losing most of your progress from one day to the next is disheartening and also a problem we need to solve, but I don't think making it so top-ranked players cannot keep slowly climbing if they're investing in it will help people in the 1100-1800 VP range.
This is basically the stance of the designers at Nodding Frog; multi-hit having multiple chances to proc talismans was never the intent. We will be fixing this in advance of PVP going live, because it's becoming increasingly clear that this one of the biggest factors that pushes the game too far into "go first and win" territory, which is inherently anti-competitive.
It's something we're considering, but it's a fine balance to strike. If the damage reduction is too strong, durable Sentinels and damage shield status effects (Reflect Shields, Damage Reduction Shields, Magma Shields, etc) start to become way too powerful, making certain characters unkillable machines (there's one character in particular that we have concerns about, much to my chagrin). We want to look into options that could allow players to do this if they sacrifice other opportunities, but are not sure how long it would take to implement such ideas, which may instead come out around or after PVP goes worldwide.
For the most part, the most likely case we've anecdotally seen with people having teams 50-75% crushed in turn 1 usually boils down to one or both sides having glass cannon teams (which works well in PVE when you're just strong enough to do that to enemies, but is a lot less consistent in PVP) or is fighting at a rank well below where someone should naturally be. We're still gathering and analyzing data to see how widespread this is at various divisions and to help us guide VP point gains and losses to help naturally push people into ranges of points that best fit their power and skill levels.