I've ridden in the Alps and Pyrenees with nothing lower than a 39/25. There were certainly some moments where I wished for something a tad lower (more often in the Pyrenees than the Alps) but that was what I had so that's what I rode. I lived in Paris at the time so I was training mostly like you, with distances about what you do. I'd think that the 34/27 would suffice.

[Edited to add:] My FTP at the time was pretty pedestrian, probably about 3.3 watts/kg.