I would be perfectly fine with them giving back the health regen, giving back the shield length, and taking the damage buff off of ult. She did not need a buff to her ult damage in any way. I am a riven main at D5, animation canceling is not her problem. There is no way to take away the animation canceling riven has without forcing a buff to her q and w, because then her damage would have to be spread over like 5 more seconds.
Not to mention the fact that she has literally no good meta matchups right now, other than MAYBE gangplank? She's not strong in lane, and takes good skill to teamfight correctly. Riven has an extreme, read: fatal, weakness, to literally ANY form of cc. A silence, a stun, a root, literally anything in a coordinated team will ruin riven unless that Riven player is good. This is why people like you at gold 5 hate riven, because at your rank you have teams that can't work together, have no idea what a strength and weakness is, or how to abuse it. For example, the adc that tries to 1v1 the riven and gets pissed that she cant use caitlyn to effectively outplay a riven. Everyone at higher ranks knows that riven is a bitch to fight, because at higher ranks the people that play her are dedicated riven mains who are extremely good at the champion. Viper, dekar, boxbox, are all mechanically insane with the champion, and are properly rewarded for their skill.
I'd wager everyone knows when they have a riven on their team, if it's a good one or bad one. You know immediately when the riven feeds 3+ kills in lane, and then tries to 1v3 for the rest of mid game, that they're garbage.
I'd say riven needs no offensive ratio nerfs, but I would take back the buff to her ult damage, and give it back some missile speed, if not all of the missile speed.