Buy a topography map and explore, I found so many incredible trails like that.
Get on Strava in the evening and use the segment explorer feature, mark on maps, go enjoy.
You can just ride along any of the roads and take any little path that takes your fancy, pop out at the bottom of the valley and find your way back to the funicular.
My highlights:
La Varda is a hike from the top of TransArc 2 and you can find it on Strava fairly easily. I’d take someone with if you ride it, it’s not particularly difficult (there are much more technical in the valley) but it’s very exposed. Watch out for walkers too.
Likewise, at the other end of the resort, on the north facing slope, is Double Header, it’s also on Strava. You can hop over to it from Cachette and once you find the entrance (through a little meadow) it’s easy enough to follow. Remember, skids are for kids!
There is so much to ride, there are no bad trails!