I'm a NW Plat whose now in the Delta universe. Prices are higher, seats seem harder to book. Lot's of miles/status, but I'm looking to see what's out there. I need 15k miles to lock in my Status Matched PE, by May 15. I primarily fly HNL-BKK and HNL-AMS, I'm an orchid breeder(NOT a sextourist) and I fly about 5X a year (3/2) In the future probably more AMS and drop BKK to once a year. I'm 6'7 and haven't sat in a coach seat Intl. ever, or a very long time anyway. Can't imagine it. Usually pay NW for BKK about $2300 plus miles or PU's, Delta wants $2,600-3,500 plus 50k miles, and seats seem scarce. Part of my problem may be that April is one of the worst months to fly through Japan, with their holidays there seems to be more competition for seats.
So, now's maybe the time to try UA, but with NO miles, NO certs, NO nothing to work with, except cash, my prospects seem dim for upgrades to Business. So, I tried refundable coach to see what higher class coach would get me. At least with Economy Plus seats I'd have legroom.

The first gets me 13,000 miles, still short of locking in PE. I would have to do a mainland trip to get over the threshold.
$3108 HNL-NRT(Y) NRT-BKK(Y) then BKK-NRT(Y), NRT-HNL(Y)

OR, I could do a mileage run (18,000 miles, the most efficient way to get more than I need) that looks like this;
$4317 HNL-LAX(M), LAX-NRT(B), NRT-BKK(B) then BKK-NRT(Y), NRT-HNL(Y)

I know with Plat @ Delta I can lock in upgrades at these fare classes, what's my reality of getting any upgrades with United?

Mahalo plenty