2 stock 6-7 min can be okay too, or 3 stock 10 min
I have already explained to you, that the timer should not be the same as melee. Melee matches in 4 stock 8 minutes go by much quicker than brawl matches because there are so many 0-deaths and defense is more balanced than offense compared to what brawl is. Increasing the timer would not necessarily extend tournaments at all, it would simply discourage timeouts, because people wouldn't want to GO OUT OF THEIR WAY to time out if it was not a viable way to win.
Think of 2 scenarios where scenario 1 has 1 minute left on the clock in a close game, and scenario 2 has 3 minutes left on the clock in a close game. In scenario 2, going for a timeout is going to be a hard way to win, and trying to win with that goal is pointless since it won't happen, but in scenario 1, you can just buy time and try to run away. The match may even last longer (the full minute, instead of say, 30 seconds that it would have normally took) because of that. It won't be negative for the game.
I've been trying to fix the rules for 2 years in BBR but it's always voted down (rules like, getting rid of rainbow cruise and brinstar, and increasing the timer) by the same members from BBR that kept voting to ban MK. The intentions were obvious. Both my rules would have balanced the game better, and then after 2 years (and even while IN BBR these guys said this) those same people complain about he's too good with 8 min timer, or too good with certain stages, which is what I've been trying to get rid of this entire time.