I'm a middle ground. While I like playing competitively, I like playing casual as well. They're both amazingly fun and there's lots of options to play either style in each game.
Brawl is very difficult for to play competitively due to poor balance, though. Not an issue with the rest, although I will say it has an overall better course selection over Smash 64 in return. Which had a fairly lackluster set for actual competitive play. That said, if I didn't heavily practice as Ganondorf in Brawl, I wouldn't have been able to quickly adapt to him in Smash 4 right away. Not that it won me the tourney, but it definitely helped me show just how good Ganondorf can be overall. It may also help that I didn't have many immensely strong opponents or that strong counters. But it was my first tourney for Smash 4, and I had fun. I destroyed a Link, and made the other players work hard for their wins. Even the Samus couldn't do it easily. I may have been at a severe disadvantage, but the player had to keep going at a tank to win. And it wasn't easy to take it down. XD
Melee is the only one I played somewhat competitively most of the time, but I also had some very good character options with some pretty strong balance. My main character in Brawl is Wolf, although I have no real chances to pull him out so I can't practice him much. Not an issue with the other 3 games. Brawl is really unpopular in my area. While I can understand many reasons why, it's still a great game in its own right and as long as it has a reasonable enough moveset or played who don't abuse the Ledge Grab, it's pretty fun. That said, I'm probably the only one who wishes the LGL was either different for everyone, or the same for all, so it actually is a fair rule. Many characters are different, and I don't think it makes sense for only Meta Knight to have it lower than the rest. It feels like a copout of the rule itself. Just apply it properly to everyone, or no one. Stop treating him as super special(then again, I really disliked a lot of silly ideas to nerf him. "Let's remove his B buttons!" Just... no. Seriously, that's just telling me that he can't actually be played as in some way that is equal to everyone else without treating him as overpowered by design. Not that he's balanced, but I always felt like it was a cheap way to not ban him. Either treat him as equal as possible or just ban the character. A middle ground is not needed. If he can be fought against on equal grounds and lose against you, it's fine. I won't pretend he isn't an issue overall, but these silly rules made it next to impossible to actually get better against him and further the metagame. IMO, I think this is really what hurt Brawl's metagame.)
I know it's a bit of a rant, but I wanted to get that off my chest. That said, I think every metagame can evolve if they stop putting super arbitrary rules like different LGL for one guy total. Rules do need to exist, but you need to explore the rules a lot more and try to avoid using some to balance only one character. It doesn't actually make them balanced by any means, and it's very clear it didn't even help to change up the winnings to any significant degree.