I tought the point of urf was that it was a mess of a balance?
EDIT : I read the article actually. I think it will always be a worse case of imbalance than SR. No matter how much then balance it. Unless they were to tone down the core mecanics.
I don't see it as anything than a very popular (maybe 2x per year or extra long) temporary mode in it's current form. My guess is that they can take every champ and slap a cap/balance nerf on them just to keep them form the sona-win-rate.
Maybe they'll tone down the CDR across the board. That would mean the worse abuses would be less severe (stun locks) while keeping the mode's full freedom. You an still do whatever you want, but there are less godtier.
Maybe they could inforce a global diminishing return on CCs.
Maybe they could buff Summoners spells to keep the crazyness while toning down champions. I could see flash being closer to DotA's blink dagger (1k range + 30 sec cooldown or somethign crazy like that). Ghost turning you into a rolling rammus, Heal healing for full?
In other words, keep the crazyness, but tone down champions to a more manageable level.