Ryan, I think either the Harley or the KLR650 will be o.k. for you, given:
1. You take the MSF course, as planned, and,
2. You PRACTICE, extensively, in parking lots and on deserted roads, whatever bike you start out on.
Practice slow, tight turns; panic stops; parking, dismounting, etc.
Sounds simple, but--SIMULATE stopping for fuel. Get used to the routine; don't want to awkwardly drop your bike anywhere.
Oh, yes; speaking of dropping bikes; I think the KLR will be easier to pick up than the Harley!
Regardless, you're starting out right with the MSF course; wear ATGATT (All The Gear All The Time), protective equipment and clothing.