Not sure if this even the thread for huge balance/idea dumps, but I played this basically all weekend with the best player in my area (sorry sethlon, he apparently has you beat) and introduced ARC, the rather notable Marth main, to it and ground out ideas with him, so I have a lot of cohesive thoughts to through out about the current build.
First off, ARC immediately took to Wrastor and quickly developed a super cool way of playing him (this game is amazing) that was incredibly juggle heavy and efficient. Lots of parry mindgames to take advantage of his crazy early kills with sweetspots and such. At the end of the weekend we both agreed that Wrastor in his current state has a couple of weaknesses that don't fit with the character - namely, his combos, which feel like they should be devastating and freeform, are escapable fairly often even with reads. ARC's suggestion was to increase hitstun by a minor amount on either fair or uair (I think fair, the juggles are already pretty complete) so that air dodging out isn't as easy. He also said that downb, which he used extensively as a combo extender/chaser, was a great move but felt 'unreliable', as though it could be DI'd by more than normal, keeping him from reliably following up on it. Also, he gave up on neutral b as anything but a runaway because if he tried to actually damage me with it I could always hit him out of the end, with any member of the cast - the last hit just doesn't do any stun. That could be intentional to keep it from being a viable off the top kill move, though.
My own thoughts after such a serious time of grinding out matchups amongst the current 4:
Kragg has the potential to be the least fun character in this game by a wide margin, mostly due to his neutral b. It's a projectile leagues better than other characters have, and just having the block near him gives him such a huge advantage, matchups seem to polarize around it if the Kragg player wants them too. This feels especially rough on Orcane, who has a tough time breaking the block or getting around it once it's out, and has a tough time threatening Kragg consistently enough to make him scared to pull it often. The other two have easier, if no more diverse, matchups against a campy Kragg; parrying and aggression make it more than doable, but playing against Kragg just has the potential right now to be unfun in a way that the game otherwise avoids.
On a similar note, a Kragg with a pillar nearish the stage who has time to pull a block is in a pretty absurdly powerful position. I really think that blocks shouldn't be able to be pulled out of his pillar. It does not fit with the game's stated goals and is just generally annoying to deal with.
Orcane is generally super amazing and fun but has a couple of weird feeling things that don't feel fitting to the character's theme. Most noticeably, his upair feels like a pretty randomly good kill move that doesn't fit the trap/control theme I get otherwise. I'm not sure how to keep his kill potential the same with the theme still in place - something else to convert bubble mines to kills quickly, maybe just make his upair only that strong if he's in a bubble field? - but it would feel much cleaner thematically if that happened. Or perhaps make him an even stronger edgeguarder somehow?
We also came up with character designs at 4 am for the remaining 3 - Ice Emperor Penguin that is glacially (heh) slow but has a ton of traps/stage control, a jungle/tribal themed monkey with a longstaff because a fast earth character and a disjoint character both sound cool (although forsburn seems to have plenty of disjoints so this might be less necessary), and a Japanese myth style wyvern with a focus on movement/dodging. All of these sounded amazing after about 26 horus of no sleep.