Here's a powerful shove on the positive side: versatility!
Penelope by itself (same rhythm as
Elizabeth, which nobody minds),
Penny (fine), Nel or
Nell or
Nellie (varying degrees of fine),
Poppy (trendy right now, and my least favourite, but not bad) - and the associations with Mrs
Odysseus are wonderful.
Just one thing that might tip you on to the other side: I used to know an
Yvonne Frances whose nickname as a baby was Squeaker for obvious reasons. She became known as
Penny Squeaker, and then as
Penny, and had difficulty recognising herself as an
Yvonne. But then some of her friends started playing around with
Penelope and came up with Lopes! (As in I lope, you lope, she lopes; not like Lopez.) Of course, the chances of that happening twice are pretty small.