First off, I would recommend not using any Nori.
I would still use a bit of rice vinegar with extra honey or brown sugar coupled with the milk. (make sure the sugar/honey cuts the vinegar odor, if you have to add a bit of salt too) it should help keep it sticky.
I think you may want to keep it alittle more simple, for example, the mango pineapple would be good with a little honey dip (1/2 honey + 1/3 milk) (or drizzle honey) but the strawberry sauce may be good on the side too (personally, id love to try it, just wouldnt want to use alot).
I love the strawberry banana /choco drizzle idea, Im so trying that.
I hope my advice helps alittle. Great ideas here!