Many of us have gone through these pains. You can modify your seat for about an 1" or 2" max. You can have the suspension professionally modified as well.
I would guess that the majority here will tell you to learn to ride it as is. Once you do you'll really come to appreciate what the bike is capable of.
Search the forums. It's a well discussed issue.
2013 KTM 1190 Adventure
2007 KTM 950 SE
2004 KTM 450 EXC
1979 Suzuki GS850
1993 Harley Café Project