I consider a lot of things you listed as cons to be pros.
+-1 MM is what I've been arguing in favor for on WoT for years. It just blows to be stuck in a +2 game where it feels helpless to play against the higher tiers, especially when you're already in a tank that has a weak gun for its tier.
Less tanks means less complicated trees which I consider better for the game overall. We don't need 12 nations with 100 tanks per nation. Since this falls under your last variety point, as well, I'll point this to your last statement as well.
You shouldn't fucking be TKing people regardless of how shit they are, unless they're actively blocking your path (i admit, i did it a couple times on WoT, the most infamous example being the whole RDDT incident). On 7v7 maps that could easily handle 12v12 this should never be an issue.
I prefer this game's maps, with the exception of Mines. I hate it on PC, i hate it on Blitz.
You also miss seven things in the pros column that I consider worth noting:
* The game plays faster because it's 7v7 on smaller maps. There's no big stalemates where you're waiting 5 minutes just for something to develop. Prok on PC feels like a good example of this. Teams basically plod along until someone makes a move on hill or lights make a mistake mid. That simply doesn't happen on Blitz. Engagements happen within the first minute; the 7 minute time limit forces you to act
* An extension of the above: The 7 minute time limit means that you can slip in a game while, say, you wait for your coffee to brew, or while you're waiting for (event with an arbitrarily short time) to happen. It's really nice to have a game you can slip in and out of easily.
* Everything costs less- gold, premium time, premium tanks. The IS-6 is roughly $50 on WoT proper and around $30 on Blitz. Prem time is cheaper as a result of the prem time costing the same amount of gold but gold being cheaper. With the gold they start you with, you can get a t7 on sale with $10 put into the game and still have enough left over for a t3 prem later on.
* It links to Steam, so you can use Steam wallet money to buy stuff. Turn all those dumbass cards you get from your Humble Bundle games into tanks. It works.
* No XVM or XVM focus means everyone is just playing against everyone else. Someone purple would never have to worry about being focused; I, as a shitter greenie, don't have to worry about being ignored. People just play, man.
* Crew skills are different, in a way I like. You don't have to have a barracks of 120 crew members based on the tanks you want. Every tank is treated as using one crew, and what skill you train is based on the class you use. 6th sense is on by default for every tank, which idk if that's been implemented into WoT proper since I haven't played in about a year, but it's a huge development to me.
* Consumables are a lot less expensive, and more streamlined for what they are.
Overall I like the pace of Blitz much better. I was frustrated about long, drawn-out games on PC with expensive consumables. You can buy a premium tank of whatever nation you want and it'll benefit all tanks instead of just the tank of that nation and class, and the reduced money investment for premium stuff offers a greater appeal to a wider audience. At the very least, it's worth going through the first few tiers to see if you like it enough to invest more into it. I enjoy it more than standard WoT, and I'll likely be buying an AT-15a- a tank I wanted on WoT but couldn't afford- on there this weekend with leftover Steam credit.