I am going to be making mini cupcakes tomorrow for a family get together Saturday, I want to do a few different flavor combinations but want it to be simple. Any suggestions??

I was thinking just make them all vanilla/white cupcakes then fill and ice them with different flavors,

strawberry lemon
coconut lime
strawberry coconut
lime strawberry
lemon coconut??

How could I do this and make it simple, or does anyone have any other simple flavor combs that can be switched up but are simple to make?
Any one know of a watermelon cake recipe?