200-250mm is a popular focal length on 4x5, but 250mm may be pushing the limits of bellows when close to the subjct. Hence the suggestion of the 10" tele's.
The commercial Ektars are Tessar types, but partially because they have a modest max aperture of f6.3, they tend to perform better than the Tessars. I highly reccomend them.
Dagors are slightly soft wide open, (great for portraits) and bleeding sharp stopped down a bit. They are a very versitile lens, but expensive.
The convertable Symmars inexpensive.
Really I would suggest you try the 135 first to get a feel for it. I bet you will be surprised how nice it is for portraits.