Gold Dynamo might look like a big deal on paper, but considering how bad it was before, I don't actually think this saves it. The problem with Chumps isn't their speed, it's that they just aren't doing very much.
In terms of what's relevant, I think the real biggest winner is either Custom Douser or Sorella Tent. These are already very strong weapons to get bumped up further. Douser is definitely going to be a monster in this patch, farming more Strikes and being able to use its Burst Bomb a bit more easily. Tent, well the entire Brella class needs to be reevaluated now, it's hard to say how big of a buff it is but it definitely is a buff. Honorable mention to Carbon Deco as another high tier that got buffed further, but not by as much.
For weapons that were on the cusp of viability that might see more use, S-Blast 91 and Sorella Brella are worth keeping an eye on.
We'll see if the Big Bubbler changes actually matter for vRoller, Jr and Mint Decav, but I don't think they really will. Not like you can react to a Zooka with it.
When it comes to low tiers that might potentially rise the farthest - while probably still not actually rising all the way to meta - that's gotta be Recycled Brella Mk 1. Brellas may in fact be real now, 20f is a lot of frames to shave off its regen time, and the Big Bubbler buff is there too I guess.