Certainly seems more like a "catch them up with buffs" patch rather than a "knock them down with nerfs." Lots of underplayed heros got some pretty substantial buffs.
Abaddon - Turns him into a true tank. I could see him as a counter to deathball or AOE strats. A 35% damage shield on your whole team is no joke.
Bounty Hunter - Buff to track range could easily tip him back into play.
Brewmaster - Autocrit makes him an even better initiator.
CK - An extra illusion could help him get online sooner. Not sure if it will help him get any play without Wisp, though.
Void - Already getting some notice. A better turn rate make him even more of a beast inside chrono.
Jakiro - Buffs across the board. He's always been a good teamfighter, and a 14 second 1800 range macropyre is no joke. In a siege you could effectively shut down a whole side and force the enemy to clump.
Kotl - Aghs looks to make him a beast. Free spammable mek, nightstalker's agh's vision, plus permanent ghost form at any level? Where do I sign? Easily one of the best Aghs upgrades. I could see him becoming a top tier support just because of it.
Lina - Becomes pretty much a hard counter to lots of carries until super late if she goes mid. By the time the carry gets BKB, she will have aghs and be able to put them out of commission in any fight. Could definitely see her getting play in certain situations.
Necrophos - He's already a strong hero, but hasn't been trending. 30% death timer increase and 200 range on heart stopper will definitely attract notice. If you take down a bought back level 25 carry, that's going to be something like a 200 second respawn time and probably a guaranteed win. He's also going to be an absolute terror in pubs. Could easily see him having the highest pub winrate this patch.
Omniknight - A bunch of little buffs that will get him noticed. With aghs, 10 seconds of global physical immunity is no joke.
PA - Buffs will make her early game a bit stronger. Probably not enough to push her into real notice.
QoP - Buffs to shadow strike make her an even stronger mid. Not sure if it matters without more changes to bottle crowing.