Just a quick idea that one of my friends made: simultaneous battles.
It would involve multiple small squares/circles/dojos as "mats", spread apart, where in each one, two players would go up against one another. If you are to land outside of the area you were placed in (including another mat) you would be eliminated. It could also function as a ladder; the victorious players would move on to the "next round", where it would continue up until there are two left, where they could fight to the death.
Another idea that I made, derived by the extra people battling at once, is team battles. Team battles, as you'd expect, involves 4+ players, equal amounts on each team, pitting against one another. Once all players on a single team are eliminated, or the time runs out, the team with the remaining players (or more points) would be victorious.
One final idea I have is "multi-battles". It involves 3 - 4 players, all against one another. This one could lead up to great chaos, and, other than the extra players, it would function as a normal battle. It could also be used together with the idea of simultaneous battles and/or team battles.
Been suggested many times, and was actually possible for a while, it however proved really buggy and slow.
Maybe eventually we'll see it but most not some time soon.
(1st idea) hmm... did some thinking. How about a story mode/endless with alot of fighting and training u to do stuffs for the new players and new different types of moves and techniques
(2nd idea) waiting in queue can be time taking and boring. if u can make a 3 or 4 players or make waiting in queue more exciting than just watching lots of players fight cause some fights are extremely boring and it can cause people to leave because of waiting in queue (especially if Tb gets famous and there's alot of people)
hmm think that's it im done XD like the ideas that popped out this genious brain you might like them
Experience
Well duh it's been suggested before the thread is 4 years old. Commenting on an old thread that has been left open is not a violation of rules/stickies, the moderators would close it down if they saw fit to do so. Also the thread you linked to show that the idea had been turned down is this exact thread you commented on. They were giving their input/support for the idea. And as dannyrug said it isn't impossible, technology is constantly improving.