imo
- Sceptile suckith but current moveset is fine
- Blaziken should definetly have speed boost, dual STAB + Protect + Swords Dance
- Swampert should have Stealth Rock and HP Investment over speed
- 4th should be Bulky Mega Salamence,which handles Blaziken (the most threatening of the 3 starters)
- 5th could be Tangrowth to handle both Sceptile and Swampert
- 6th could be Porygon 2 for other mega mence