I feel that way too. I understand Mum's logic in wanting to use
Monica nn
Nikki; okay, fine, if it can be made to work and you like it and it's what you want, go for it. But it will have to be "made to," i.e.
forced to, work. I agree with you, Chrisell, about how awkward a nn seems when generated from any but the strongest sounds in the name. Well said. :-)