How are your steering bearings? Put the bike on the centerstand or jack it up to get the front wheel off the ground, then slowly turn your handlebars from left to right looking for any notchy areas. My nighthawk had a bad feel to it before I failed inspection for head bearings, swapped them out for tapered rollers and it handled so much better. How're your wheel bearings??
I remember when i took the MSF course one of the bikes I rode had a horrible feeling of shifting sideways when you'd change lean direction past center, I figured it was swingarm bushings, I'd hate to have tried riding that thing faster than 15mph.