I was listening to the Kled voicelines and how like funny they are and thought of Rammus only saying ok, yea, right and mhm. I don't know if this can even be answered since the time frame they were recorded but was there anything else Rammus was going to say? Like no or just nothing.
They actually addressed this before. Rammus originally had a 'real' vo planned, but it got delayed to a point when they didnt have much time to finish it, and the end product was apparently a really bad southern accent. So they scrapped it because they werent satisfied, and as a joke just make the VO he currently has, they expected it to just be a place holder, but lo and behold they never got around to replacing it.
yeah
I wasn't around when Rammus 
was released, but the fact that all he has very little Dialog is one of his defining traits at this point. If they did give him dialogue, it just wouldn't be Rammus anymore, if that makes sense.
Also if Rammus sounded like this in my games, I'd run for the hills. https://youtu.be/zrn2K4eFl5g
I think it was a bug or something at the time. In other languages he has a lot more lines, but they didn't make it in the english version. It just kinda stuck and it's now part of who he is. I'm curious to see how they'll handle the VGU if there's one.
