I believe you can disable the nagging change up indicator. As you said it’s pretty pointless as it’s not the sort of engine to lug around in 4th to 6th gear at slowish speeds. I found the GSA rather top heavy even without panniers, and was the main reason for selling (apart from not needing a 750GS and 850GSA) but it did feel remarkably similar to a lighter 1200GSA in terms of all day comfort and range. I would consider a lowered model now that a centre stand is available from SW Motech (or for static maintenance a low profile roller platform) - the extra weight of the GSA might help offset the overly-bouncy rear shock on the low 850GS I initially owned; however you do lose the ESA, which is a shame as, although rear-only, it seems to work quite well.
I found both the stock and “comfort” seats rather less than all day comfortable. The Wunderlich seat I replaced it with wasn’t cheap but it’s like night and day - flat, very comfortable, no higher than stock, a cutout in the middle to relieve pressure on one’s privates and bizarrely it seems to be better at locking into place than the OEM seat.
I found both the stock and “comfort” seats rather less than all day comfortable. The Wunderlich seat I replaced it with wasn’t cheap but it’s like night and day - flat, very comfortable, no higher than stock, a cutout in the middle to relieve pressure on one’s privates and bizarrely it seems to be better at locking into place than the OEM seat.