Early gearboxes on the 1150 with the E gear had the taller 6th. All other gearboxes had the same final ratio and shifted the revs up 500rpm in 6th.
When I got my 1150adv I thought the e box was better, but now think the standard box is more useable. Not as good on long motorway slogs, but better on the twisty everyday roads.
E box first gear is the same as the standard adv box. The adv had a low first option but most bikes came with a standard box. I've off roadbed an e box and it was fine, but you do work the clutch a bit harder until you get the confidence to go a bit faster.
If you are only doing road work then the easy option is to fit a different bevel box to change the gearing but it will effect all the gears not just 6th.