Mana Pool definitely needs to be increased to 75. But I wouldn't go further than that. If he can't do his thing he's literally useless, and there are far bigger balance issues at the moment.
I had a game with
at level 3 in an ideal comp with _6 mages _ as well.
I thought it beforehand as soon as I've noticed that I had enough pieces to build around it, so i started collecting
rather soon.
But unfortunately I gathered only 5 and couldn't find the 6th, nor could find the 3rd
to complete the build.
At top 3 though, I noticed he didn't even need it, he would instantly (with a bit of luck) oneshot 2 units as soon as the round started and he was able to recharge his ability in like less than 3 seconds! Not to mention the fact that 2 mages are Ocean (which I'm not against, but they are quite strong on their own too, especially
), so sometimes if the timer was up as soon as he was done with casting his ability, he'd do it again back to back. I think I've recorded it too.
Not gonna lie, it's funny to see him oneshot units instantly and hear him laugh, but mages are just sliiightly op, the whole aspect of using their ability twice can be all good and fun on some champions and completely broken on others.
They should be adjusted to like 50/80% chance to cast their ability again, or whatever.
I've recorded a couple of funny videos of what happens when units with cc abuse the mage trait : https://www.youtube.com/watch?v=bahGDiQH_X8