I take it you don't main Yoshi. The Eggroll gives only a couple frames of lag when its broken, and has quite a bit of priority now (IIRC it clanks with MK's whorenado). If used properly, it can punish spot-dodgers and deal shitloads of damage to enemies with low jumps like Ganon and Link. You can also pressure with it, which is pretty nice. I'm not saying its one of his best attacks or anything, but definitely a good move to rely on when you're just starting out and haven't quite learned the DR or any of his epic combos. Also, I take it you're referring to the Dragonic Reverse when you say "Yoshi wave dash". DRing is ridiculously hard to execute, I wouldn't recommend trying to incorporate it in a beginner's Yoshi strategy. Also, its completely unnecessary for landing jabs, since the dash can combo into the jab on most characters at low damages (against Bowser you can combo it until like 80 damage lolololol). And nair should NEVER be spaced, the closer you are the more effective it is. And fair should only be used off the ledge, as a spike (it can actually be combo'd into, which is nifty for 0-deaths) or for DI purposes.