Hi guys, I'm new to this forum and this is my very first post. I signed up because I felt compelled to assist. (OK, this is an old post but I wanted to put my 2 cents worth).
About 6 months ago I was hell bent on buying the 50/1.8 because I wanted a bright/fast lens, but then I saw Sony come out with the 35/1.8 and I was rejoicing because this lens was PERFECT for me. I did like the idea of the 50mm but felt I would not use it as much due to the focal length.
Fast forward to today, and I own the 35/1.8 and I LOVE IT. It's the lens I use in most situations now. I am just a casual photographer and the 35mm is perfect for that.
The main advice I have for this particular comparison is that the 35mm is a more usable focal length if you want a walk around lens. 50mm would be better for portrait and sports in my opinion, however landscapes and indoor photography is better suited to the wider 35mm.
You can't have a fixed lens that does it all, but I say it's the more usable of the 2 lenses in question. F1.8 is perfect for indoors, yo uare better of with the 35mm indoors, especially if you are in a smaller house. You can't just stand back with the 50mm if there is furniture, etc in the way.
So I say go for the 35mm because you sound like you want a general purpose fixed lens, and this lens is now my walkaround lens, so it's definitely gen purpose.
I only have one problem with this lens... I find it difficult to come up with a lens kit that will compliment it well. With the 50mm, it's very easy to compliment with the usual 18-55 and 55-200. With the 35mm, I find that any wide zoom lens (anywhere between 16 to 50mm) seems like a waste of money because I would never use it with my 35mm as the first choice. At least with a 50mm prime, I could still get good use out of an 18-55 for example.