i voted for the "normal" lens category as most of the large format sites on the web categorize the 210mm as a "long normal" lens. Another great thing about large format is that I can use my so-called normal lens as a short portrait lens and a 1+:1 macro lens
Interesting results, most here prefer wide-angle, yet the mass consumer audience has been force-fed tele lengths for many years (try to to find a decent wideangle on ANY consumer digicam -- you won't!).
Which perspective do you prefer?
 Compressed space
 Emphasis on foreground
I would still vote for all four, because there are always hundreds of possible pictures to take from one point of view, but only a few that really work. Each of that few may require a different lens. Preferring a certain lens is equal to making compromises from a (most likely) different point of view. Everybody knows this from practical limitations, too. If I have to limit the number of lenses and if I dont know what subjects to shoot in advance, I would prefer following order (for 4x5):
4 Lenses: 90, 150, 210, 450
3 Lenses: 90, 150, 300
2 Lenses: 90, 210
1 Lens: 135
From this, you may conclude that I do not expect to find many subjects where an ultra wide lens might be the right choice. On the other hand, if I know that I will be shooting Architecture or flowers in a garden, I would certainly take a different lens set.
For me a 210mm 0n 4x5 pretty much does it all- but my 90mm Angulon is v handy for stuff like interiors and group shots. Anyway, if I had more than 2 or 3 lenses I'd be spending way too much time wondering which one to use and probably miss lots shots!
This is relative to 4x5 only. I have a 65, 90, 150, 210 and 300mm lenses. I use them all, but the 150 and 90 get used the most. The 300 is starting to sneaking up there though. I would love to get a 47mm and a 450mm but that would require me to buy a new field camera, something I'm not prepared to do at this point. It's the old 80/20 rule. 80% of your pics are taken with 20% of your lenses.
For me it seems to be a toss-up between normal and slightly wide. I gues that treatslates to 50/35mm in 35mm film, and 150/135mm in 4x5. But usually it just boils down to what the heck I have handy at the time.
My lens choices used on 4x5 are as follows- 150mm most (50%), 90mm second (30%), and finally 240mm about 10% of the time. I also use a 355mm and a 480mm but those are not used in a shutter and are at the maximum length of my bellows draw so they are only used when the composition screams for the compression or the distance (across canyons photographing Native American ruins) is so great I have to use it.
I've used wide a lot lately, revisiting some places I just couldn't use "normal". So lately it's been about 40% 90mm on 4x5", 121mm on 5x7". Rest "normal" to moderately long (135-210mm on 4x5", 210-360mm on 5x7").
My next lens will probably be a smaller 300mm I could use on the 4x5", or maybe a 450mm.