Also, note, for me, thermals on the rifle, still have two purposes, spotting and shooting.
My "go to" gun for night purposes, is a colt 10.3 upper with the 35mm Mk3 on top. This system can id hogs out to 1200yds (done that) on 2x black hot. Though for me shooting standing up, this is a 300yd system best case, though usually under 100yds. So while I rarely shoot over 100yds, I spot out to 1000yds and further, often.
It is the spotting use case, where I sometimes wish I had the 60mm .. .but for shooting, on the land around me, I prefer the 35mm, greater FOV. On 2x, the 35mm gets the job done, though as an LR spotter, the 60mm would definitely be preferred.
So the answer depends, as always, on your use cases. If you spot out to 1000yds or so much more often than you shoot under 100yds ... or if you hunt with a buddy who has a 35mm, then one guy with a 60mm would be a good compliment.