Here's my opinion on nerfs and buff that should be added to each character.
All his attacks he gains way too much AP and it's way too easy to just run away while damaging other opponents. Nerfing AP gain would make so his AP bursts don't activate. Instead, I think they should change the amount of AP required to get his level one, level two, and level three. Drake needs far more AP than Sackboy does getting all three of his levels yet every single one of his levels are worse, he gains overall less AP.
Level 1 should require 50AP more. Level 2 should require 50 AP. Level 3 should require 100 AP more. Decrease level three time by 1/4th or decrease it by 1/5, make the prize bubbles hold less, and make allies gain no AP when attacking enemy bubbles.
Grenade should blow up quicker(almost useless as it is now.) Tranquilizer should have a longer range and/or last twice as long.
Level 1 should require 50AP more. Kratos should not be able to attack in one direction and turn the direction of his attack around mid combo if other characters can't do it. Example, square one direction. If someone rolls behind you, hit the other direction and continue your second and third square, still hitting the opponent. Chain grab should have no homing. Toro's Get Over Here attack has no homing.
Sly's electric roll should give 5-10AP. Every other time Sly is in a game that's all he does. First off. Some characters are difficult to counter this due to how fast the recovery time is. Parappa, Fat Princess, Sweet Tooth, Dante, Virtua Fighter Toro, etc. The other thing is that many people are good enough to counter this cheap tactic, but you're still playing 2v2 or free for all.
On free for all, you can't guarantee that anyone on there is going to be as good as you are. You might be able to defend and counter against Sly's electric roll, but he'll still gain up to level three in two seconds because everyone that you're playing against keep going after him but have no idea to defend and counter against his cheap tactic. 2v2 but not as much, you only have one ally who may or may not be as good as you.
Nothing. Although maybe add a little bit more to the recovery time on the uppercut so you can hit confirm into level one. As it is now, there's no guaranteed hit confirm.
His upward swing while on the ground when hitting an enemy should have a slightly longer recovery time. As it is now, it's just short of being able to hit confirm into a level one special.
His level two special should have more homing added to it. It also seems sometimes all the glowing balls can sometimes follow the exact same enemy player.
His level three needs to be longer.
It really sucks that you have to use a combo to guarantee a kill with your level two on a 1v1, but playing against any skilled players, dodging Toro's star, even on the smallest stage is ridiculously easy unless you have the enemy coming out of a combo. The star should have a bigger blast radius.
Easiest hit confirm into a level one. Should require 50 more AP because of how cheap it already is to acquire. Charge punch should lose all power if not used in a certain period of time.
Shorten the time of his level one. If you don't get the people in the first second or two, the other four or five seconds isn't going to make a difference. The special going on for so long is worse for Ratchet.
You're either going to use ground square starting off, or air square or forward square. He should have less recovery time for his attacks. As a comparison, Kratos has fast recovery compared to Dante(compared to anyone really) and his attacks are from 10 feet away. If someone misses with the ground square, any of them, it's very punisheable. Kratos can spin around in mid attack and continue his combo as well(Dante can't do that either.)
Remove his level 1. No seriously. His level one is ridiculously easy to combo into. The fact that you only have to grab the opponent to get a full combo, you are guanteed your level one the next attack.
Kidding about removing his level one. However, change his grab by making it knock you to the ground so you turn invincible and not being able to do a full combo every time you grab, also removing the ability to change direction while using his attacks.
Never played, but from what I've seen, nothing.
Nothing, only because I suck with him.