It sounds like the wide FOV, lower mag binos are themselves a very effective piece of gear. Might have to get my hands on some to see if they're worth the potential trade-offs on the higher mag end of things. Right now, I carry NL 12x for an everything, Goldilocks binocular. There are times when it would be beneficial to have a wider FOV, and times when a pair of 15x/18x would be advantageous. But I'm a weight weenie, so having one pair of binos that covers everything quite well has been nice. For higher magnification I've carried an STS 65 with a 30x eyepiece. It generally goes along for any deer hunt, plus the odd goat/sheep hunt.
Weight-wise, the downside for me would be considering 15x binos to be mandatory alongside the low magnification ones. Maybe for some elk or bear hunts they'd get left behind, but for almost everything else the 15x would be in the pack. The secondary kicker to that is it almost completely negates the likelihood of taking the spotter also. Probably need to just play with some to decide. I have some old Habicht 8x30, but their FOV isn't really any wider than the 12x NL.