Originally Posted by hokiefyd

Having mismatched brake levers will definitely sour things. A lever intended for V-brakes pulls more cable length, and has less mechanical advantage, than a lever designed for cantilever brakes. If you use it with cantilever brakes, you won't be pulling the brake cable with as much force, and the brakes will feel like they're trying to grab a wet rim. The opposite is equally bad -- a short-pull lever (for cantilevers) matched with V-brakes, if you could even get it adjusted so the brakes wouldn't drag, would pull the cable with so much force you have a much higher risk of going over the bars. Ideally, you'll be able to match the brakes with the levers. That is, replace the lever with one designed for short pull brakes (like cantilevers) or replace the brakes themselves with V-brakes.

Keep in mind also that the MultiTrack 700 was the lowest model in the 7xx line, which means it has the lowest percentage of butted chrome-moly, and the highest percentage of high-tensile, steel in the frame. In general, bikes with more high-tensile steel are heavier and less flexible -- the bike will, as you describe, handle or ride like a truck. If you got on a 750 model, which has a chrome-moly fork and fairly flexible butted chrome-moly tubing in the frame, it'd feel like a different bike.

Regarding cross-chaining, I've always had pretty good luck with front derailleur adjustment (this is where I presume your chain rub comes from). I usually adjust the front derailleur with it in the middle position, and turn the barrel adjuster so that I traverse the entire cassette or freewheel on the back without any rub on the front. I've never had a bike where I couldn't do this. A 700 should have a 7-speed freewheel, so you should be able to find this adjustment okay. The front derailleur is then generally pretty good in terms of being able to drop down to the small ring or push up to the big ring. You may have chain rub if trying to ride in small/small, or big/big, but that's often going to be the case. Not that the bike was "designed to do that", but that it's simply the nature of trying to cross the chain over so far. The derailleur cage has to be narrow enough for good shifting and also wide enough to allow for some degree of cross-chaining. My 750 has Shimano STX derailleurs index-shifted with modern Shimano RS47 Revoshift twist shifters. It has a 22-32-42 STX crankset and I'm usually in the 32 or 42 ring in the front, and then usually in the lower half of the cassette on the back. I don't have any chain rub, but I would say that I'm probably more cognizant than average about chainline, and I do try to keep it relatively straight.