50/34 will get you plenty of range and low gears. I'd probably replace the 50 with a 46 so that you're better setup for cruising in the big ring. You don't really need super big gears. I'm currently touring on 46/34 with a 12/25 cassette and it works fine for a light load. I may go to a new derailleur and a 12/36 sometime, but don't feel the need yet.