I really like the name Christian, but as someone else with a Gabriel who introduces him as "Gabriel" yet people still refer to him as "Gabe", I'd say if you're really not liking Chris as a nn, you may want to go with something else.
I wouldn't let it dissuade me if I loved the name, but it seems like it bugs you. FWIW, I love Benjamin, too.
For girls, I like Georgia and Meredith the best. I went to school with one Meredith, and she didn't have a nickname.