Re: Ukemi makes you (feel) tougher...
I wouldn't agree really, If anything, they make you less tough because you're not getting at all hurt when you fall!
improving my ukemi was the thing that started to get me going in aikido, it's all in the relaxation I think. When I was a white belt, I was the classic plank of wood, but my ukemi improved and once I learned that I won't get hurt, my whole body relaxed more and from then I could actually start learning something.
Though I still get a bit tense at inappropriate times which makes my technique suffer, have to keep working on it!