I would say try different things as well. I would do another vote for martial arts too but keep in mind from my own observation and personal experience, kickboxing may get stale at some point as well because there are only so much you can do in terms of techniques compared to standard martial arts where you have an unlimited number of forms (including weaponry, which I specialize in) to discover.
But kickboxing can be fun so it's worthwhile to incorporate into your portfolio of activities. You might want to revisit some past activities too as sometimes you just need to take breaks from them.
If you live in a winter region with snow, I would most definitely suggest an outdoor winter sport as well. And once you take on some sports that you really like, you can approach your general fitness workouts as supplements to help you perform better at your sports. That's what I do to get through my general fitness work which usually is not as much fun as the actual sporting activities. But at least with that approach, I still do them.