Hey buddy!
I'm not an expert at this and still have a lot to learn about the Advanced world, but I'll give this a shot.
If there is a move with the same accuracy but higher power and your Pokemon can learn it, always go with that move. Don't take Aurora Beam over Ice Beam. Also, try to steer clear of moves that have poor accuracy. Having a variety of different types of moves on the same Pokemon is always handy, but try to make sure that you can protect yourself as well. Offensively, your team is strong, but defensively, it appears vulnerable.
Quite a few of your moves are reliant on one status change. For example, your Houndoom needs Sunny Day to pump up its Flamethrower and Solar Beam. However, what if you were up against a Dugtrio? Two Earthquakes and you're done. You'll never get a chance to use the Solar Beam.
Also, Gengar with Hypnosis, while handy in the game boy, is not a good idea for battles with others. Hypnosis only hits about once every other turn. Plus, there's the chance the foe will wake up before you get to use Dream Eater, and then you're out another turn. If Gengar is paralyzed, you're done.
Replace Scizor's "Slash" with something better. Critical Hits negate stat boosts.
Salamence with Earthquake sounds good. It's too bad, really, that it can't learn Ancientpower. That'd be a very good 4th move. Even Brick Break would be nice.
Flygon? A second Dragon-type, with 4x weakness to Ice. Yowch. That's why I suggested Brick Break on the Salamence, you know. Crunch, Earthquake, Dragon Claw and hmm... why not something like Protect? Just in case you go against someone with Sheer Cold, etc.
I'll let someone else take the stand from here. It's no fun if I get too into it.