Alright. I'd hate to say it, but there are quite a few problems with your team here, seeing you are most likely running in the OU Tier. Luckily, I can help you out :D
For Lucario, he is best with holding Life Orb to give him a well needed power boost. Also, Lucario is not meant for bulk, because he can still be easily be OHKO'd by almost any Fire and Ground move. Here is what I would recommend:
Lucario @ Life Orb
Trait: Inner Focus
EVs: 252 Atk / 252 Spe / 4 HP
Adamant Nature
- Close Combat
- ExtremeSpeed
- Swords Dance
- Ice Punch/Crunch/Stone Edge
As for Charizard, he does not work well in the OU Tier. If you're looking specifically for a fire type sweeper, I would go for a Pokemon like Infernape:
Infernape @ Life Orb
Trait: Blaze
EVs: 64 Atk / 252 Sp. Atk / 192 Spe
Naive Nature
- Close Combat
- Fire Blast
- Grass Knot
- Hidden Power Ice
Now for Garchomp. As for him, you should never run a Frustration set for Garchomp imo, because he has many other talents that could be put to better use. Also, try not to always use Shell Bell and spread out EVs for bulk, because that wastes potential for that Pokemon. There are many sets to be used with Garchomp, so here are a couple of them that would find most use on your team:
Garchomp @ Choice Band
Trait: Rough Skin
EVs: 252 Atk / 252 Spe / 4 HP
Jolly Nature
- Outrage
- Earthquake
- Fire Fang/Aqua Tail
- Dual Chop
This set utilizes Garchomp's immense power and great coverage. Choose Fire Fang over Aqua Tail for sweeping common walls such as Ferrothorn and Forretress, and choose the vice versa to counter Rain teams, seen almost as often as Drought Ninetails in current metagame. Also use Dual Chop to break through any Substitutes to get in your way.
Garchomp @ Leftovers
Trait: Rough Skin
EVs: 252 HP / 196 Def / 60 Spe
Jolly Nature
- Stealth Rock
- Dragon Tail
- Earthquake
- Fire Blast / Aqua Tail / Protect
This set I would prefer, seeing your team mostly utilizes sweepers and would need a support set like this. However, this team does has an excess of Special sweepers and get walled, so the above choice could also be one to prefer. He is best used as a lead with natural bulk and set up Stealth Rock, using Dragon Tail to dish out some individual damage. Fire Blast is to wipe out any Steel type in combination with Earthquake, and Aqua Tail once again for Rain. Protect is simply used to scout out Choice users and safely switch in.
At this point, you need a spinner. Based on your team as of now and Ferrothorn being out of the question due to heavy presence of Drought, I would run Starmie:
Starmie @ Life Orb
Trait: Natural Cure
EVs: 252 SpA / 252 Spe / 4 SpD
Timid Nature
- Hydro Pump
- Thunderbolt
- Ice Beam
- Rapid Spin
Use Hydro Pump rather than Surf imo because of Rain presence. Or, you could use Donphan as a better lead and also great spinning capabilities.
Donphan @ Leftovers
Trait: Sturdy
EVs: 252 HP / 252 Def / 4 Spe
Impish Nature
- Rapid Spin
- Earthquake
- Stealth Rock
- Ice Shard
I would definitely prefer this over Starmie, as long as you run an offensive Garchomp and Aqua Tail for Rain revenge killing.
Now, we come to the point that your team is almost entirely sweepers. Where's the love for walls?! So now, rather than Alakazam lets go with a well needed Reuniclus. Even as a partial wall, it can still well utilize sweeping and Magic Guard.
Reuniclus @ Life Orb
Trait: Magic Guard
EVs: 192 HP / 64 Def / 252 SpAtk
Quiet Nature
- Trick Room
- Psychic/Psyshock
- Focus Blast
- Shadow Ball/Hidden Power Fire
Use Shadow Ball to counter a Ghost weakness, and Hidden Power Fire to counter Bug. 'Nuff said.
Now, for a bulky water type. Although you do have Swampert,there are other Pokemon like this that better play this part in OU. Not only can a Poke like this utilize Rain, but can also hold its own against a few Pokes on a Drought team (obviously not Ninetails or Venusaur however). Let's go with one of my faves, Rotom-W.
Rotom-W @ Leftovers
Trait: Levitate
EVs: 248 HP / 28 SpA / 232 SpD
Calm Nature
- Volt Switch
- Hydro Pump
- Thunder Wave/Will-O-Wisp
- Pain Split
This set is meant to counter SpA, so it works well in weather. Use Thunder Wave to cripple common threats that would try to switch into Rotom, especially Venusaur. Use Will-O-Wisp to counter any physical attackers, but I would sooner use Thunder Wave as the better option.
And there it is! Hope you have some fun on Showdown!