Her cooldown on the ult I can understand, but I seriously did not notice that her health regen was really that high. And it really saddens me than you log in, you play a game, you get first blood, and kill the person 2-3 more times (before ult) and they complain that Riven is overpowered.
You think its the champions fault you wasted all your resources, and I used the simple strategy of minion swarming to attack you? Hey, you are taking massive minion damage, deal with it. But no, same thing with Zyra, QQ QQ QQ and more QQ always the kids get what they want. The same mechanics apply to Riven and Zyra, don`t want to get hit? SIMPLY MOVE OUT OF THE WAY! And of course I personally thought her late games fails hard. She dies super fast even in a off tanky build if focused... and her dmg is kinda bleh, but she can still kill carries fast (like its supposed to be). I thought that a 0.1 or 0.2 scaling on her ad would make her more competitive. I never seen her in pro plays yet, then again I have only played this game for 7-8 months or so