I'm also 6'3". I have the 330mm YSS shocks on a mid setting, but also had the seat re-trimmed to remove the king/queen step and increase the height a bit. The 80/90/100 gives more seat room, but this helped a lot.
(BMW Traditionalists look away now)
Also cut and welded the left foot peg so it aligns with the right and my size 13 boot can select all the gears easily now.
I would not go very far off road on an R65. The sump will hit over anything like a tree-root, rock, large stick or branch etc. As you said, the bean can is also low and that front cover is just a dust/splash/beauty cover. The GS has a couple more inches clearance, even standard.