i have a giant rapid 3 that was only 549 bucks and is crazy fast flat bar bike. I don't know anything about ability to install panniers though. I'm 6'3" 245 lbs and live in nyc where our roads are terribly potholed. if you know your route will have decent quality roads that is a help. I'd be sure to outfit it with tires that can take 100psi of pressure vs 85psi which is what the stockers on my giant were. I replaced them with Cannondale Armadillo kevlar laced tires which were 50bucks a pop but the reviews for being "flat proof" were excellent for them. As for number of spokes on the wheels, many would say that 225 isn't all that heavy and that riding you'll drop some weight. At 6'4 and 225 it sounds like you really probably don't have much weight to lose though but stock wheels should treat you right. below is a pic of my bike. xl frame, very comfortable ride. I'm new to cycling and on week 2 I was taking it on 20+ mile rides for fun and had no issues with comfort. I will say that it is addicting and I'm already looking to get a dedicated road bike to really whip aorund on so I can put larger tires on my Giant and make it a bit more pothole proof.