Team Gai was pretty much the perfect team
When you think about it, Team Gai had a lot going for them. I think that they're the most capable team of producing pretty much any results they want to, given the effort.
Their leader weilds the 8 Gates, strong enough to take on Sage Naruto and possibly pain, has a very strong will, and is closely tied to his students. Plus, in some Shippuden scenarios where all 4 of them are around at once, they're almost invincible because of their amazing teamwork. Team Kakashi... isn't very functional together, they usually just break apart with each of them doing one thing on their own, or Kakashi and Naruto are working together (and even then, Kakashi is usually trying to keep Naruto calm). They don't use much team cooperation in their battles, they don't work together (not to say they can't, they just haven't shown their teamwork to be as strong as Team Gai's). Team Kuranai (if that's how you spell her name)... hasn't really been shown taking on anybody as a team since part 1, and even then they were partnered with Naruto, not their teacher. In fact I don't ever remember seeing her working with Kiba, Hinata or Shino, they're pretty much a student managed team. Team Asuma is... kind of not possible, sooooo..
But aside from teamwork, they have the perfect team with all the advantages. They have a long distance fighter (Tenten), a close range and very strong/fast fighter (Lee, who also has access to his gates), and a defensive fighter who can also make very critical close range attacks, and if given the chance can pretty much paralyze opponents with the right hits (Neji). This is why I think Team Gai is the perfect formation.