Honestly the only good customs we have are Thunder Wave and Heavy Skull Bash. The rest is either not good, needs further testing, or is outclassed.
Thunder Shock is bad. Loses the versatility Thunder Jolt has, which lets us camp and get a free grab if the opponent shields it. It also loses the paralysis effect Thunder Wave gives, all for a horizontal blast that KOs early, but is it worth giving up the versatility of Thunder Jolt and paralysis shenanigans of Thunder Wave for TShock?
Quick Attack's customs aren't worth using, especially Meteor QA. You move slower, which lets opponents gimp you (ahem, Cape, F.L.U.D.D., Hydro Pump) and is overall poor reward. You don't gain anything by using this move. I could see it being used for things like Thunder Wave chains > Meteor QA on the ground > Thunder meteor but eh, it's just not worth it.
Quick Feet is niche at best. No second jump, could potentially be edgeguarded, eh. Even though it has the same hitstun and startup as Quick Attack, it hits opponents at a good angle to hit with something else. So yeah, niche.
I won't bother talking about Thunder's customs. Everyone knows regular Thunder is better.
