upgrade advice for budget-minded beginner

I was looking for some advice on possible upgrade paths. I'm new to this A'gon community and want to get the most out of my "investments" since I'm a college student with limited funds. Currently, I have B&W 602s with an old Denon DCD1000, Yamaha M-60, and a Kenwood pre that needs to go. My noise floor is just awful, the highs are very forward and bright, and alot of music sounds lifeless and overtly digital.
I was considering the Onix reference 1/SP3/XCD88 combo for $1500, but wasn't sure if the Ref1's would be a huge step up from my 602s thus justifying the purchase. Also, I've never heard a tube amp, and although the characteristic naturalness and soundstage abilities seem to be what I'm looking for the supposed lack of woofer control and low wattage make me a bit nervous.
Another option I was toying with was keeping the Yamaha M-60 and adding an Eastern Electric Minimax preamp and possibly CDP to my setup hoping to take the edge off the highs, open up my soundstage, and eliminate background noise.
Basically, I was wondering what people that have more experience with this hobby think would yield the most "bang for the buck" in my situation. I want a deep and broad soundstage, natural sounding mids, musical highs, and authoritative bass but don't want to spend an arm and a leg to get it (like everyone else, I'm sure!). I'd appreciate any input, and am sorry about the length of the post.