The Boeing 787-10 should be a significantly better ride than the 737-700 in economy.
1. 787 has modern AVOD entertainment on every seat. 737-700 only has Live TV best case, which is over a decade old.
2. 787 has 31" pitch, 737-700 has 30" pitch. Even though it's only a 1 inch difference, The 787 seats are slimmer, which means more legroom.
4. If you get a 737-700 with Live TV, there will still be entertainment boxes and dividers underneath the seat. Those boxes really eat up on legroom.
5. Personal opinion: the 787 cabin is much nicer. Larger windows, quieter, more overhead space, higher humidity, mood lighting.

For me, it's a no brainer.