I do have LPS in 4k via the Columbia Classics version. If I bite on this release, I would just pick up the less expensive Blu-ray-only set and skip the 4k.
I haven't seen Texasville, and have only ever heard mixed-to-negative things about it. Hopefully they'll stream it on the Criterion Channel so I can try before I buy.
Texasville would be my only reason for buying this, as I have two copies of Last Picture Show already: Once in Criterion's BBS box set and once (twice actually, since it includes two versions of the movie) in the Columbia Classics v3 4k box.