I need a new bike (don't we all?)

my 'Old' Nighthawk 650 is giving my fits and I'm getting kinda sick of it, not that I'm going to get rid of it (that would let my girlfriend feel like she's won the battle) but I'd like something more reliable, maybe faster too if I can get both for under $4-5k... I'm a pretty fat guy, working in that tho, so I don't really want any thing too sporty just for comfort... don't really want a Harley ,because they're expesive and some are slow... what should I get?????