I nickname everything I plan on using.
Crush - my Scizor
Cloe - my Starmie
Asuka - my Gardevoir
Bowen - my Gallade
Fred - my Ludicolo
Yuuji - my Aegislash
Wargale - my Braviary
Fleur - my Lilligant
Valentine - my female Charizard(Y) - based on a weird dream whee I had a Y charizard-like dragon pet born on v-day
Fangflame - my male Charizard
Ender - my Chandelure
Jetfire - my Talonflame, uses it's own version of Oogie Boogie, even if unreliable at times.
Shane - my Bisharp
Kyuubey - espeon female
Madoka - Sylveon female
Homura - Umbreon female
Sayaka - Vaporeon female
Kyouko - Flareon female
Mami - Jolteon female
Takato - another flareon, male
Hellburn - my Houndoom
Gremlacks - my sableye
Oyuki - my Frosslass, not really a creative name due to the japanese folk tale/legend she was based on.
Rekka - My rash Magmortar (it's a role play of my darkside)
Brohawk - my pansear
Broette - my Simipour
Brotupe - my Simisage
Annoyance - my fly+dig Flygon (note I personally would ride a flygon if i must choose any pokemon as a mount)
Aurora - my Togekiss
Amalia - my Celebi
And many many many more....
If I'm going to use it, it has a nick-name, so there's likely one for every Pokemon in the dex, even if the games wont let you rename it. As you can see with flareon though: some have more then one based on their sex.
EDIT: not to mention but all of the listed above named pokemn are in lux balls, except Asuka who is in a love ball. (Shut up.)
Crush, Asuka, Jetfire, Annoyance, Fred, and Aurora make up my main team in-game. With Crush or Asuka likely to mega-evolve. Though any of them can be swapped out for any of the others on a random whim.