Note: I don't know how Brawl+ is being used by most people, when I use Brawl+, I'm talking about directional airdoging, s-cancelling, and no tripping.
Brawl+ becoming the official way of playing?
No, I don't think that a version of Brawl that requires a decent amount of computer skills should be considered the standard. To most people the hack might seem childs play compared to some of the larger console hacks out there, but I've seen lots of gamers that can't do much more on a computer than surf the web (and even then they mess things up).
Should Brawl+ have tourneys?
Yes, I personally enjoy playing Brawl+(WD,S-cancelling,no tripping). The no tripping part explains itself. S-cancelling is one of the major reasons I keep playing Brawl+. Getting rid of the aerial lag greatly increases the offensive capabilities of the characters, which makes the whole game move faster. I don't think we would need to improve the hitstun in the game, because with the faster followup resulting from s-cancelling and the lack of multiple dodges from the directional dodge mod, it is a lot harder to avoid attacks in the air.
This next part is what makes me think that most people haven't tried the mods before rating for or against them. Wavedashing is nothing like it was in melee. It is very finicky about where you start your dodge to do your wavedasy. If your a little to early you just hit the ground and do a side dodge. If your a little to late you won't retain your momentum and will just stick onto the ground. The reason I like to play with the directional airdodge is for the reduced aerial defensive strength, rather than the ability to wavedash.
Does Brawl+ need SBR/SWF approval to have tourneys? (Sorry if I'm not as professional on this part.)
No, the only thing that Brawl+ needs to become worthwhile to competators is a playerbase. If there are people that want to participate in Brawl+ tourneys, and there are people willing to host a Brawl+ tourney, there are going to be Brawl+ tourneys. Sure, there aren't going to be any MLG sponsored events for Brawl+, but I can still see enough of a playerbase that a person who solely trains on Brawl+ won't be dissapointed by a lack of tournaments. I'm pretty sure well even get some big tourneys if the mods flesh out a bit more.
So, I guess my answer to the topic title "If tourneys approved hack?" is, if tourneys approved hacks, then people that enjoy these mods will attend these tournaments.
and the corollary...
If a tourney doesn't allow hacks, people that enjoy Streight Brawl will attend these tournaments.
Different tastes for different people.