[REQUEST] My first team

[shinybluebird]

This is my first time trying to make a competitive team. I just got into competitive teams so I am not that good at explaning teams .
 However I hope I could get some help in building this team and learn more about team building 

This is my team :

Mawile-Mega @ Mawilite
Ability: Huge Power
Level: 50
EVs: 252 HP / 204 Atk / 52 SpD
Brave Nature
IVs: 0 Spe
- Play Rough
- Iron Head / Fire Fang
- Sucker Punch / Rock Slide 
- Protect

Mega Mawile is one of the Megas I always wanted to use. So I decided to make a competitive team around it.
I chose a trick room Mawile because it could do some massive damage if it gets the right speed support. So the supportive pokemon I chose was:

Jellicent @ Colbur Berry
Ability: Cursed Body
Level: 50
EVs: 252 HP / 180 Def / 76 SpD 
IVs: 0 Spe
Relaxed Nature
- Trick Room
- Water Spout
- Will-O-Wisp
- Recover

I chose this Pokemon because it could deal with groud and fire type and deal with some physical attackers too.
The second trick room user I chose was:

Gothitelle @ Sitrus Berry  
Ability: Shadow Tag  
EVs: 252 HP / 12 Def / 244 SpD  
Sassy Nature  
IVs: 0 Spe  
- Psychic  
- Trick Room  
- Helping Hand
- Protect

I had a hard time choosing between Bronzon and Gothitelle because both are good trick room users. I'm not sure if I made
the best choice, but I didn't want to deal with two Pokemon that has a weekness to fire.

My second offencive Pokemon I chose is:

Conkeldurr @ Flame orb 
Ability: Guts 
EVs: 252 Hp / 252 Atk / 6 Def
Brave Nature  
IVs: 0 Spe  
- Mach Punch  
- Rock Slide  
- Bulck Up
- Drain Punch

I chose this Pokemon simply because I think it would do some massive damage to 
dark and ground types.

The last Pokemon I was thinking of is:

Rotom-Heat @ Life Orb  
Ability: Levitate  
EVs: 252 HP / 100 Def / 136 SpA / 20 SpD
Modest Nature  
- Thunderbolt  
- Overheat  
- Hidden Power [Ice]  
- Protect

I thought that Rotom - heat would be good because it has resistance to ground and can 
deal with flying or grass type.

Are there any suggestions for the 6th Pokemon?  And are there any parts that I could fix for a better team?
I would appreciate any help for the improvemet of the team