To quote something i did see here earlier:
"Rock needs to be nerfed, paper is fine" - scissors.
So you did find UB to be more powerful than Rook? I dare to say that you didnt play Rook the way it is meant to be played. There is no way UB causes a rook any trouble, that is.. inside his little garden of towers. They will spit and then run away quite fast as the towers will eat them. If they decide the chase, you just hammer slam.
Hammer slam is weak? 1700 AoE damage is weak for you? Hell, it starts out with 500!!!! damage on level1. Sure it is slow, but that can also be used as an advantage, as you can easily cancel the ability if you see the enemy is running away from it.
In fact, a hammer slam is the perfect psychological weapon against most demigods early on. When they see you raise your hammer, especially if they are fighting you inside your garden, they will just run away and by the time they realize you didnt slam, they just took too much damage to continue fighting.
Also.. you have 3 independent weapons next to your fist and abilities, each of which is capable of killing enemy demigods if you are lucky.
Still, with the rook, your task is not the killing of demigods. You can just go around the map removing enemy towers and quite frankly, if you do your job well, they will need at least 2 very good, or 3 average players to remove you from your lane. If you get backup during that fight, then they are just screwed and will have to withdraw.
So my advice: learn your characters before you judge about how balanced they are.
Hell make HoL remove spit. It wouldnt heal you becasue you would take 1 sec of dmg, but at least it could remove spit. There needs to be a universal non-favor counter.
Sorry, but WHY exactly NEEDS there be a counter? Is there a counter for the TBs fireball? Is there a counter for the Sedna pounce? They are all just damage dealing abilities, that in addition deal INSTANT damage. Spit is just a Dot. It can kill you if you are low on health, but even then it takes time to do so, which gives you plenty of time to counter it, and countering it means lots of thing: porting home to the crystal (takes about 3 seconds), drinking a health potion (takes 0.5 seconds), etc..
Use your damn imagination and realize that theres healing beyond heart of life and abilities in this game.