Re: Why no tsuba?
I prefer using my buokken with its tsuba. I like the feel and the obligation to stay on the handle. But I can, and sometimes do, remove it. especially when training with a group that mostly don't use it.
The design considerations mentioned don't hold if you shop around. i have a hefty large enhanced hickory aikiken from Kingfisher that I had fitted with the bamboo tsuba which looks good on the bokken and is very functional (thick and solid).
This is what you need if you do those paired exercises in Chiba's style where the strike is landed against the hand/tsuba.