Another vote for the 24mm Panoptic. Something about that eyepiece, I keep returning back for it.
Have a 10mm Pentax XW and 17mm Nagler.
Another one to consider could be the 20mm Scientific Explorer 100 degree FOV. Haven't used or seen it personally, buy reading some articles, its got favourably reviews and a hell of a lot cheaper than the 21mm Ethos. Just bear in mind the weight.
BTW: the 24mm pan is a 1 1/4 barrel size.
Cheers, Norm