Tower rook isn't OP at all, except on Crucible where he's retardedly imba. Think about this for a second - when you play against a tower rook, and he's setting up farms in one of the lanes, what is he constructively doing? Sure, he's creating a trap for any DG that tries to take him out, but any decent player should not be stupid enough to do so. He'll farm creeps, but if he's only in one lane, then you can kick his rear end easily, cause you can cap more than one flag. If he tries to challenge, he's most likely useless without his towers, unless you've let him farm so much that he outlevels you by 5. If that happens, it's not a case of rook being OP, it's just a case of you stinking it up.
Just play like that lane doesn't even exist against a tower rook. He'll slowly move up, sure, but one of your towers can keep him back well past level 5, and you should have a good lead by then. Heck, cap lock his portal and tele around. IMO a straight tower rook is stupid. Early on, when most other DG's are squishy, towers are very good, but mid-late game rook's have to go with some BR/HS or they'll get embarrassed.
I don't really agree with this post at all, though I'm glad to see it because I'm an avid rook player and am more than happy to see people opposed to nerfing him.
I honestly have no idea how someone would even make a "straight tower build." What does that even mean, just nothing but stats, towers, and structural transfer?
Also I find Rook to be even more powerful on Leviathan than on Cataract and he's quite effective on prison as well. I honestly can't think of any maps he's bad at, certainly not any of the popular ones.
That's because towers don't count as Rook kills. If he isn't near the tower, he doesn't make gold or xp. They also die after a short period.
I think this is only part of it. The other part is that you can summon four yetis/shamblers, 2 monks, siege archers, and minotaurs in the time it takes to set up a second tower, and Oak/EB can summon a whole army quite quickly and either completely passively or with the press of a single button.
At later levels when a rook can have a large amount of towers up you're seeing 50% or more of every fallen enemy being raised as a minion until those DGs hit the cap, so the time it takes the summon, the mobility of said summoned creatures, and the mana costs are so wildly different that I think the persistence after death is justified.