Swain as of the Update
So I personally love Swain's concept, I just never played him much because he was rather weak. Now, with the new RoA/Catalyst, he's actually pretty dang strong I would think. With Swain being a battle mage (i.e. Getting all in the enemies' faces taking damage and dealing it out) he can actually use his ulti to great effect with the massive healing you get and the mana regen from being in the thick of everything. That, combined with the new Morello can get you some major mana returns in teamfights thanks to the 20% on kills or assists.
So thank you Riot, I think I'll go play one of my favorite champs some more.