Great project, I can definitely feel the effort and thoughts put into the game.
So to make it better lets get in a bit about combat flow and enemy design. The devil is in the details after all.
I'll assume you have at least played one dmc games within 3/4/5 to decide to make this, so I'll use direct reference of skills from those games.
If you pay attention to Dante's rebellion combos, you'll notice that when performing Combo B's spin-around 3 hit attack, you can cancel out of it anytime with jumping, dashing and blocking, after the 1st hit lands.
My understanding is that this is to compensate for the long duration of Combo B, that you can opt out of it within reasonable speed (hard locking only the 1st hit).
Another important fact about Combo B is that it hits all around Dante as he swings rebellion from the right hand to the left. Against common enemies that guarantees hit-stun, and thus Dante's safety when performing it.
These two points are what makes Combo B work even with a long animation and not that much damage to it. It can be cancelled, and it has a 360degree reach.
This is to contrast in YMC's current version, Gura's 2nd melee press in her Combo A hits 3 times, all to the front (and does not track enemies too well), and is non-cancellable.
Especially when combined with the fact that the current enemy roaster tend to attack pretty fast (especially the shrimps), it makes Combo A very dangerous to perform, with little extra benefits, whenever there are more than 2 active enemies on the field.
So to me, improvements to the combat would either be to slow down the enemies' rate of attacks, or to equip player characters with a more versatile or responsive move set. Especially a double jump would help a lot. Even greater help would be some good long iframes when the player is being knocked back, so that they can't be stun-locked to death by a couple of Tako-spins or KFP fly-pans.
My current experience besides just spamming ranged zaps of the trident, would be to only use 1st hit of the trident ComboA, then switch to twin blade aka Agni&Rudra, or try to launch.
Naturally connecting to the topic of launching and air attacks, you may realize that in dmc3/4/5, especially 4/5 Nero/Vergil, their air combos actually has really big hitbox, way beyond where the physical reach of their already giant swords .
May not be so realistic, but it is to compensate for hitting multiple enemies, and the slight distance/height errors that often happens when both parties are falling at different speeds.
So yes, a bigger hitbox in the air would be my suggestion. Of course I do notice the existence of Payline/air stinger present in the game, but I see no reason to limit the viability of other attacks because of that.
It also would compensate for the player character easily moving backwards away from the target because he held the back button during the launch move, although I would add that a more fundamental solution would be to recreate dmc's High Times completely, where holding the back direction after high times still would not move Dante backwards by much at all.
Gura's agni&Rudra launcher also seems to have a much shorter reach than the Trident, which may be in need of some adjustments.
There are things that can be said about every move, but I hope that going in detail on just two examples can give a clear picture about the fundamental concept of it all.
So if you're still planning to improve this game for a little bit, I hope these suggestions could be of help. Nonetheless thank you once again for making a good HoloXdmc game!