I still have yet to try Squad battle. It's basically ranked with the teams locked in place, right?
Yes. You squad up with other players from your Wii U friend list, so you can have 2, 3, or 4 players, and you're always teamed up. The problem is, you play with only other squads, so sometimes it can take a bit to find a match (you go back to the lobby every match instead of staying with the same players until you/they quit). If you have 2 people then another 2 squad will join your team, and you'll face a team of two 2-squads. If you have a full squad of 4 players, you will face another full 4 squad, or... unfortunately, the 3-squads are mixed in with the 4s, so if you have only three players then you'll face a lot of 4s and it'll always be tough.
Another thing is that your ranks don't matter as much in finding opponents. It will attempt to match you with squads of similar ranks to yours, but if it does not find any, it will match you with whoever it can find. This means that even back when I started out as a C-, I still ran into A and S players. So the competition is way more fierce than any other mode, which stinks, but oh well. It's the only way I can team with friends, so it can still be fun.