going with a 60t and 11-34 cassette is something I wouldn't do because of the immense jumps between gears. it'll leave you wanting more inbetween gears.
I guess don't mind moderate jumps -- I tend to make big multi-gear jumps anyway. And in truth to get subtle changes that you can get out of a DD (like a front-rear derailleur combo) you have to change interleave changes in both shifter, and I just don't do that. Plus a DD is just too crazy expensive for me.
So given a choice between 11-32 and an 11-34, which would you pick? The 34 gives me 29.8 gear inches (the 32 gives me 31.7). But the jumps on the 11-34 are bigger, especially that 11 to 13 jump. Specifically:
11-32 jumps like this (11 to 32): 9.1%, 16.7%, 14.3%, 12.5%, 16.7%, 14.3%, 16.7%, 14.3%. It's basically exactly like the standard 8-speed 11-28 presently on the Tikit, plus an additional 32-tooth at the top.
11-34 jumps like this (11 to 34): 18.2%, 15.4%, 13.3%, 17.6%, 15.0%, 13.0%, 15.4%, 13.3%
That big 18.2 and 17.6 aren't great I guess. Which would you pick?