Can we get Martial Arts?

Well no need for many martial arts styles, I would rather see them do one martial art really well than do several poorly. 

My suggestion would be to add boxing as a full sport. Like add a ring where sims can either do a friendly sparring bout or a competitive fight. They could also work as a freelance boxer or such, I don't see it being a whole career track, their standing and earnings just determined by how often they win. 

In the same pack, Sim Fu returning as a martial art, maybe with some new options. Since it is no particular real martial art, it gives them liberty to borrow from all kinds of styles. And this would be a new skill that also unlocks new interactions over time. Like doing a nerve pinch to knock a sim out for a little while. Meditate, punch through tougher blocks for training like in sims 3. Punch out candles, run across a pool over the water. Do a back flip. And indeed a move inspired by the five point exploding heart technique, but not lethal since I don't see them letting sims kill each other directly. It could just be this ultimate martial art move, that they don't automatically get at level 10 but have to do more for it to learn it. When they hit a sim with it, you could pick one of several effects it could give. Like knock the sim out for 24 hours, drain all their needs to be near empty, or randomise their traits into new ones.

And lastly, I would add sword fighting. The animations are already in the game from Journey to Batuu. Only needs different weapon draw animations and sound effects. Swords could be displayed on walls, sims could have favourite swords, and there could be a whole fencing competition. Could also be funny if lightsabers cut through swords if sims attempt that kind of duel, ending it right after it begins and now the sword would need to be repaired. But swords made of a specific metal could go against lightsabers. 

There could be a new object that is a bit like the sims 1's stage. Maybe like some sort of LARP arena or such where sims can play fight or do it seriously, they would interact with the area during the fight. Like a table and stairs they might fight on, maybe a chandeleer to swing from. If Sims 1 can do it, I could see Sims 4 doing that even better. And it could be done either with swords or martial arts. The object could have several styles, stairs, tables and such always of course in the same location for the choreographed animations, but it could vary from a castle, a Chinese tea house to even a star wars inspired set.