Yoshi gives me a ton of problems. Even after getting used to R.O.B.'s slight range reduction (R.O.B. also lost air speed with Robo Burner and one of his best tools, f-air, isn't as good to land with now), I still find that Yoshi beats R.O.B. in close combat and juggles him very easily. His jab props R.O.B. up into the air where, at close range, he can't do anything beside the nerfed f-air (and Yoshi's nair is faster, so they almost always respond with that and proceed to lay on more pain). He can keep you in the air with eggs too and can beat most of your landing attacks with his anti-air standard attacks like up tilt and up smash. Speaking of the eggs, they neutralize Gyro, so trying to hit him with it from afar isn't an option.
When fighting Yoshi I try to stay grounded most of the time and spam R.O.B.'s jab and down and forward tilts but that only gets me so far because I have to get really close thanks to the aforementioned range nerf. I use weak laser too, and if I have Gyro charged enough I can follow up with that, but simple shielding beats both of those. And your anti-air isn't as affective as Yoshi's because he has a few extra frames of super armor on his double jump (there's armor even after the fluttering animation ends O_o) and can land safely with n-air or even d-air (and d-air is a free 20-something damage in most cases). Even if you shield, Yoshi can use his excellent air speed to distance himself just far enough so that your grab (which got a nerf in range) doesn't reach him. If you're still shielding or if you attempt a grab and miss (which is likely),
he can grab
you.
I really feel like I'll do better against Yoshi in the Wii U version, where pivot f-smashes will be easier to perform thanks to the C-stick. F-smash gets me out of a lot of trouble with Yoshi but if I time it wrong, he can powershield and punish with Yoshi Bomb or a grab. All the hard work you put into getting Yoshi off the stage rarely ever pays off thanks to his super armor and insane aerial mobility, which helps him through R.O.B.'s back air (another one of his main KO moves).
So help.