I thought I'd share this since I don't typically see a lot of feedback from this part of the game.
So this week I've been playing a bit on an alt account I once started years back. It's solidly in 2* land, the only noteworthy characters i have are about 5 baby 2* champs, and a 12-cover dr strange hovering a bit above that around level 120.
I've noticed that a majority of the match-ups the PVP matchmaking algorithm serves me with is matches vs players who bring along one or two 1-cover 5* character.
This is really.... not fun. The 5*s are (usually) not a problem because of their powers, but because they can tank a lot of damage (their HP pool is typically 2-6 times the size of my 2*s, depending on character and boost list) and their high match damage. The last part means they can more or less match-damage you to death, and don't even get me started about the instant wipe if they luck into a crit tile during a cascade or something.
Taking these on either results in a wipe because of mentioned problems, or takes ages to complete if you're lucky enough to survive.
Skipping only helps so much because it keeps cycling the same targets.
I wonder if a mechanic where the non-required characters have to be 1* or champed would fix PvP at the 2* level. Or whether players are in 2* land such a short time it doesn’t matter.