Is, I'm told that in the UK, Heather is more of a grandmother's or older name than a young person's. Hard to picture.
I've known three Veronicas, and none of them were called Ronnie/Roni. One of them is called Rocky. She got that name because when was about six she was struck by a car near her mailbox and nearly died, had to learn to walk and talk all over again. The physical therapists and/or nurses started calling her Rocky because she fought so hard and so successfully to recover. She's a teenager now and is only really called Rocky by her parents, sometimes.