[X] The nest you were born in, hidden under the brambles.
[x] Teach. You have a new litter of siblings, and the last few Pichus from your own littermates could use your help in pushing past the last barrier of evolution. If nothing else, they'll be allies.
She can always travel later on, right now teaching her family how to protect themselves from being captured and raising hell like she is doing should be a top priority, she has seen just how far somre trainers can go for a good catch.
If she just up and disappears they Might decide that trying for her litter would be the best play to see if any of them have the same potential as her, and if they do her family is pretty muvh screwed.
So yeah, teaching first, travelling later.