What team is better? Am i doing right?

Your team is absolutely terrific. You will hear a rather skewed view of strength here since I would wager most who post are understandably hardcore.

If what you list is your main team then I imagine there isn't much you cannot do in this game right now depending on what your area is like competitively.

Adding a few other high level mons is always good too. A Lapras makes life much easier for dealing with all of the Dragonites most of us face.

Machamp can really drop the hammer on lots of defenders that most of us see in gyms.

You mean Line up? For attack or Defense....?
Well your current team is an attacker list i guess.... and they are good too...
Sometimes if you got bored try some good pokes... Then enjoy the game...

It is a generalist's team. It should work fine for almost all gyms.
I have some specialists too, as jolteon, exeggutor, vaporeon, flareon, lapras, venussaur, machamp.

Maybe i am a bit faster when actually fighting, but you are faster when selecting your team. :-)

If you want to improve your generalists team, look out for a Blissey.

Well, your dragonite and snorlax are boss. There's no improving from those two.

Gyarados is good. It wins neutral battles faster than vaporeon, just with less health remaining.

Tyranitar, Iron tail is not so good for attack. You may want to re-roll for a bite one.

Your team (presumably for attacking) is excellent and any player will be happy to have your attacking lineup.

The only possible weak link is your lack of a Tyranitar with either Bite/SE or Bite/Crunch.

There are also great attackers/specialists that can improve your team even further and you can look into catching/hatching/evolving some/all of the following:

1. DT/H Dragonite
2. Hydropump Vaporeon
3. Bullet Seed/Solar Beam Exeggcutor
4. Fire Spin/Overheat Flareon
5. Thunderbolt/Discharge Jolteon

Good luck!

Do you only fight gyms by yourself? If you fight with other players occasionally, then adding in some pokemon with multi-bar charge moves can help. Multi-bar charge moves can be used sooner/more frequently and waste less energy/damage which are both really helpful when fighting with teammates because fights are faster and shorter.

I really like:
Vaporeon with Aqua Tail
-I have three now powered up higher than my highest Hydro Pump Vaporeon and a forth that I am considering since I use them for both offense and defense. Great against Rhydon and Tyranitar.

Exeggutor with Confusion/Seedbomb
-My old reliable defender that sadly never places high enough in gyms near me anymore but is a great generalist, albiet a bit difficult to dodge with. Extrasensory or Bullet Seed would be a bit easier to dodge with and Bullet Seed would give a double grass moveset that could be used against Vaporeon. Solarbeam deals more damage, but has a lot of potential for wasting some of that damage against any opponent other than Snorlax or Blissey.

Gyarados with Bite/Outrage
-My frequent go to now against Dragonites because it takes so long to scroll down to Lapras.

Team is awful. Probably best that you transfer them all for the candies and start fresh. That way your new pokemon wont be corrupted by how bad your old ones are