Former AP here.
A welcome basket is always wonderful.
I'd add in some water and snacks because you can be shy when you arrive ...
I'd advise not to go overboard from the start even if the girls now all sadly compare what they get.
A genuine girl will be happy with a warm welcome (balloon and drawings from the kids) and a nice little basket.
Something I have always enjoyed as an AP is when the family takes some times to show me around when I get there or organizes a nice outing/meal out so we can all get to know each other