For fist charge, not really tbh as far as something to cancel into it. She doesn't have anything that puts them down long enough to get it safely, it seems more like a distance dependent thing to keep it safe. I'm testing against Reptile's dash though so slower wakeups might give better options. I'm thinking of setting up fist charges after combos you can't run cancel combo, like f2~bf2, finishing with bf1 to put them fullscreen and fist charging. Might get blown up by teleports, I'll have to see.
As far as ground pound, this is probably the best variation for it. Fist charge (even level 1) makes ground pound unblockable, though it gives it a little bit shorter range. So I'm trying things like jp/jk cancelled into gp, mixed up with the fakeout if they read it and try something. Also, jp/jk into gp does NOT seem to be interruptable, even if you hit while higher in the air, though it can be blown up by armor. However, the fakeout is safe, so if they make the wrong read and try to armor you can block and punish.
edit: they can also backdash that, but you can punish with the fakeout with bf1. whether you can do that on reaction will come through experience, i can't tell enough yet.