Southwest has no "extra legroom" seats although they're an inch roomier than UA's. With that many points on both carriers, you probably experienced the in-flight products. Connecting airports are PHX, OAK, LAS and SJC. To handicap prospective load factors - i.e., available seats when you board - is next to impossible. Fares tend to fluctuate until about 54 days out, although Hawaii may be an exception.

I find moving about in-cabin easier on a 752. There's more more bin space on a Max 8.