Just lower Shen's Ult cooldown already
You can buff his damage all you want Riot, when a champion is supposed to truly shine mainly through his utility ult, he should be able to do so more often than once every 3 minutes or so if an electric squirrel can have one of the most tide-turning ult in the game at a fraction of the cooldown along with a self-buffing mechanic.
If you fear he'll once again become the #1 must have support in pro play again, then fine: buff the hell out of his ult but give it a scaling range instead of keeping it global. This way, it'll be more usefull in solo rather than being the perma kill-cucking machine that he is in pro-play.
That such a "weak" ability with such a long cooldown is STILL getting gated by pro-play after all this time really is saddening