I think the culmination of increased travel for all sports (in time/length) had/has the inter webs chatting about this concern.So what sports will having a west coast road trip or two a season be an issue?
There are just a handful of sports where every conference team is on the schedule each year: Volleyball, MBB, WBB, Softball & Baseball. With 16, 20 or 24 team conferences, maybe it's not important to play every school each season.
I bet there will be travel partners and schedule structure similar to what Pac12 does today. So an ISU road trip to Arizona to play UA & ASU for Th/Sat games. That same season Utah teams come to Ames. Even if the Big12 adds a couple other West Coast schools, that would be 2 long road trips every other year. Doesn't seem like a big deal over an 8-10 week period.
If costs become an issue, then the Big12 could get creative. They already do that with Volleyball where we don't play teams home & road, but back-to-back days either home or road. If playing all the other teams each year is important, maybe 3 or 4 Big12 teams come to one school's campus to play each other.
The Big12 could even use not playing every school each season to its advantage when it comes to conference tournament time. Promote east vs. west or north vs. south match-ups.
Personally, I think it’s naive to think time and money needed for athlete wouldn’t increase, and that is before the lag (EC will suffer most in this, imo).