Everyone's going to be different, but here's what I did that works well. I'm 6' also (and shrinking slightly) and I put a Cycle Gear large gel pad on the seat ($60), and then a Coleman atv seat cover ($20) on top (because the gel pad will boil directly in the Sun.)
So the oem seat (and I've got Progressive rear shock but that is only because I'm so heavy) is not bad at all. Like others here have stated, try to grasp the tank with your knees for better posture. Lean forward and ALWAYS lean your head to the rear (like on a 10-speed bicycle). Your most overworked veins and arteries are in your neck, and when you look down, you close oxygen from your blood stream and cell tissues when your jugulars collapse. Keep your back straight and constantly move up and back on the seat (randomly and as comfort dictates) so your spine never settles in and compresses your disc (that is why walking is good on your back.) And with keeping your head bowed back, pin your shoulders back and you will never need a Chiropractor for stress or posture again! (well, if you haven't crossed the 'chronic' line yet)
Last edited by kawdog; 11-16-2015 at 12:18 PM.