It sounds like you're just getting started with 4x5. Even though you tend to shoot wide on 35mm, I strongly recommend starting out in 4x5 with a normal for the format - that would be either 150mm or 135mm on 4x5. There are many, many reasons for this. I'll just rattle off a few that come to mind:

1) Many (most?) folks find that they "see" differently with 4x5 and larger formats than they did with 35mm. So, that even though my favorite lens on 35mm is the 28mm AIS nikor, my favorite, well, most used is a 135mm on 4x5.

2) Generally speaking, you'll get more coverage for the money from a normal focal length thna from a shorter focal length. This means that it'll be cheaper (by far) to buy a 150mm lens that will allow you to use camera movements than than a 90 or other wide that will allow the same movements. (I assume that is something you'll at least want to try - given the Chamonix's capability in this regard)

3) shorter focal lengths are harder to learn with - it has to do with focussing on the ground glass - I can 't explain why it just is so. It starts with the fact that shorter focal length, wide angle lenses tend to be slower but...there's more to it than that. Using a 90 or 75 mm with a fresnel screeen for example - it is harder than with a longer, normal focal length.

4) ....hmmm, can't think of more right now. You can always add a wider lens later though.