I didn't even know you can get the waxy maize with flavoring now. As far as the chalky taste, I don't think your going to be able to cover that up with a flavor pack like you can with the protein as thats just how the base product is.

TP Flavor Packs I like:
Premium Dutch Chocolate Fudge (this is the shit)
Regular Chocolate
Premium Orange Juice Indulgence

Nasty Flavors:
Regular Strawberry
Regular Grape