Back when I had DSLR's I didn't have a 35mm lens. I had a 20mm f1.8 and 50 and 85mm f1.4's. OK I could have bought a fast 35mm but I didn't
Actually my most use lens for a time was the Siggy 12-24mm.
These days I like the 35mm f2.8 because although f1.4 would be nice in reality f2.8 is just about enough and enables the body and lens combination to be very compact and light. I have the excellent Sony 55mm f1.8 but these days I sometimes find 50/55mm a teeny bit tight so it really depends on the mood I'm in
I may choose a 50/55mm for a day out especially if I think I'm going to want to take a picture of my Mrs or might want to try and fill the frame as much as possible with any interesting thing I come across like a flower or some other interesting little thing, a 50mm might be better than the 35mm f2.8 for that kind of thing and there's the perspective change too and DoF but on holiday I generally find these days that the 35mm is more of a do it all as it gets more of the scenery in
and can be used for people shots too
and all it really lacks against a 50/55mm is possibly but not necessarily the ability to fill the frame more and get razor thin DoF.
The old MF 50/55mm lenses I use are about the same length as the Sony 55mm f1.8 once the adapter is fitted so bulk wise they're ok.
To be honest I can live with anything between 28 and 55mm with 28mm being a bit wide and 55mm sometimes being a bit tight.
I have been thinking about taking a manual lens with me the next time we go to Thailand, maybe an old 50/55mm or maybe the new Sony mount Voigtlander 35mm f1.4 if it gets good reviews and if I can force myself to part with the thick end of £1k.