charizard : the thing with fly is, even with stab, it sucks. you lose the advantage of unpredictability and stuff. body slam is good over fly, or slash. body slam is good for its paralysis rate (haha, starmie!) or slash for its constant criticals.
gyarados : thunder is and likely always will be crappy. thunderbolt is better. i like substitute over blizzard, too... gets you an extra hit versus pesky electrics if you have one up. hmm... maybe it doesn't. you put the substitute up, the electric switches in. you body slam, electric thunderbolts, you flee. OR you body slam, electric switches in, you flee. hmm. well, substitute's good for other reasons too. *ramble*
exeggutor : solarbeam can be seen from something like 2038402398423 miles away. double-edge is better, or sleep powder (even with paralysis themes, not EVERY pokemon is gonna get paralyzed).
don : yes, consider rest over body slam
kazzy : people frown on tradebacks (i don't - they haven't given us any new sets that are totally broken). but the set is fine.
pidgeot : wing attack sucks in rby... substitute/sky attack/double-edge/something. double team? rest? i have no idea. poor pidgeot... it's so damn cool, couldn't it be slightly decent? =\