As a swain main, a few thoughts on his current position

Swain is weak, not mechanic wise, and not kit wise, it's mostly mana cost.

As the Heavy from tf2 would say, "At any level, it costs 1950 mana to use his ult for 12 seconds" Math wrong

With a fully maxed rod of ages, at level 18, swain has a mana pool of 1973. This is unacceptable. No other champion in the game uses mana that fast, this isn't season 2 anymore riot, this low damage doesn't justify the high mana cost.

Also, with much stronger AOE cc's, his W is completely underwhelming. It needs a change in either:

A. Increased casting range B. Decrease in delay C. Increase in AOE D. A better CC than just rooting, maybe a stun or an Amumu Ult cc.

Champions base movespeed is high enough to where they walk out of this thing, you need an outplay just to LAND it.

Make the text consistent in terms of damage per second or damage over a period. Q says damage per second while E has damage over 4 seconds. This is super annoying, make it consistent.

Q could use a small damage buff or buff on the slow, but it's still strong early game, so I am not too unsatisfied with it.