Team 7 is a really strong team at most points idk what they're talking about. Early game they don't have the high float combo yea but water element can provide that. With Naruto clones they will do a guaranteed low float>repulse>high float and Phoenix fire at the end. If you use water dragon chase as Azure Fang, then you can get that in after Sakura's high float goes off then Sasuke will Phoenix Fire.
Once Sasuke is 3* you may wanna change your Lead's chase though since he can then combo high float>low float>repulse by himself. In which case you can just change to Shark Bomb's and still have the full combo from all their characters. You can make your main heal or do damage as you see fit since Sakura also heals.