Originally Posted by theloststar

Is it a better idea to have an team with more 5* and 4* girls but that doesn't cover each attack type, or to include a couple 3* girls so that you have all four covered in each team?

3* girls will have some usefulness in the beginning, but you'll want them replaced as soon as you can with higher rarities (at least a 5*) as they will have 2 passives which helps in creating synergized squads (e.g. skill activation, attack debuff, defense/counter, shine crystal/solar drive). Generally, such squads will fare better than one that covers for each attack type.

You can check this out to roughly get an idea:
Thread: Team Tactics