I'm gonna go out on a limb here and say that I actually like Ivory Tower, even though the number of times the upper level has turned into a meat grinder is far beyond reckoning. I do wish that the open elevator in the back was more of a staircase-type affair so it didn't actually function like a murder factory, conveyor belts and all.
Otherwise, I like the angles, the mix of ranges and the effect solid teamwork can have on the map (like taking out an entire team of hallway campers in seconds by coordinating a pincher). It's not my absolute favorite, but it's certainly not bad.
I wouldn't say it's the best in Reach by a longshot either, but the framework is there for it to have really shined. It's just that Reach kind of brings everything down.