If you haven't already done so, try Kool Stop brake pads and see if they are any better than the stock brake pads. Funny the complaint about the grip shifters. Have they always been a problem? Mine work pretty well, though I have at times considered switching to trigger shifters. Talk to your local bike mechanic and see if you can isolate the shifting problem. Is it the shifters or the derailleurs? Your bike is equiped with Alivio, which wasn't bad for its time. My Bianchi is equipped with similar gripshifters (400 instead of 300?), Acera X FD (one below yours) and STX RD (one above yours).