We've both played Sheik, and I don't agree with Sheik needing to put as much effort. Sure, she needs effort to play well, but she still has guaranteed combos and 50/50 situations. One big tip for playing against Yoshi is to shield, especially at higher percents. The only thing that Yoshi can kill you when you shield is a down-B, and that is easily predicted. Neutral B only allows for damage and has no kill set-ups because you can always jump and air dodge out, and the same goes for his throws. Never jump right away when Yoshi forward throws. Other than that, you shouldn't be afraid to shield against Yoshi.
I saw some guy have his tag as "LessRolls" for his previous opponent. That seems like a nicer way to put it, and when I thought he was going to be a nice opponent when I saw that.