How about a choreographed fight routine? Sort of like "combat forms" (if you follow me). It looks good as you are still doing your moves like jumping and spinning but there is the added drama of "who is going to win".
Talk to the crowd, crack jokes (corny ones work) and generally make them feel part of the show. This will make them interested in the choreographed fight as they will be wanting their favourite person to win. You may want to have a good-guy, bad-guy thing so that the audience wants the good guy to win the fight. That way you can choreograph the good-guy getting beaten up until the very end (think Rocky).
Deliberately hype up one break that looks really difficult, then miss it on your first attempt. It makes it look twice as difficult when you succeed the second time you try. Maybe hit the board but not hard enough to break it then fake a limp, your partner must play to this and look and act really concerned.
Have fun up there, someone who is having fun and is happy transmits that happiness to the audience. By connecting with the audience (talking to them, cracking jokes etc...) they will be pulled in to the routine and will actually want you to succeed. They will ride the rollercoaster with you which is what you want.
Demonstrate some moves by having one of you dressed up in sparring gear, go over the top with the dress-up, have them padded out like never before. Then "demonstrate" the moves by kicking them. Make sure they fall over every time, if possible make sure that the audience feels each hit. They will get sympathy with the guy in the padding (especially if they are small and look weak) and then during the staged fight scene have them beat you. The audience will love their favourite underdog winning the fight.
I used to be a magicians assistant and I can tell you that 90% of any routine is hype and fluff. Magic tricks take only seconds to actually do but they take many minutes when you add in the build-up, patter and what we used to call "fluff". The trick is simple and boring (like board breaking) but what sells it to the audience is the "fluff". In fact, I recommend watching magic shows and try to see how they build up the routine. Some people use tension and suspense (escape artists) others use comedy (Mack King) and some use no words at all, just a flair of artistry (The Pendragons).
One final word of advice. There has to be a reason for doing whatever it is you do. Magicians sometimes use the "I found a pack of cards, let's use them" reason for doing a trick, some have a small story (fluff) surrounding the illusion. It does not have to be a very good reason, just one that people can follow.
I just thought of a storyline. Two people meet going opposite ways on a bridge. neither of them wants to give way to the other. They start an argument, one of them says "hold this" and hands them a board and then breaks the board. The other one pulls out a board, gets the first one to hold it and breaks it with a better kick. The board breaking escalates, each kick looking better than the previous one until finally they start sparring. Eventually they find that they have switched positions on the bridge and they stop sparring and continue off on their journey as if nothing happened.
