I think that if you did uke for the rest of your aiki career, you are bound to be one of the best aikidoka around.
If you spend 10 years falling, and you cant feel and understand everything that tori is doing to you than you have some serious problems I would imagine.
as for self defense, what better thing can you take from aikido than falling? if someone pushes you down and you fall perfectly... so what? yeah yeah, if there is more than one person blalbhabl, but the question asked in my "aikido career" not, if you had to save your wife could would you rather be uke or tori.
I chose uke, I learn more about whats going on that way.