Only ones I can think of a fitting name for. I didn't up until HGSS when I started using names from mythology, history, literature, other games and so-forth. I have a few silly or random ones, but for the most part they follow that pattern. And I don't name legendaries; a unique and mythological force of nature is above that.
Yeah i do, i usually think of the first thing that comes to mind. Usually something funny, which is in regard to their appearance, or instead their resemblance in pop culture and/or real life counterpart.
For example, i nicknamed my Magmar 'KFC' obviously because of fried chicken, or my Pachirisu 'Toothpaste' because it resembles toothpaste in my opinion, haha.
Other ones that are my favorites are:
Kricketune - HansZimmer Rampardos - Zidane (The soccer player who head-butted some guy on the field) Torterra - Gaia (The one from God Of War) Chatot - Iago (Think Alladin, the parrot) Ledian - Protoman (I see the resemblance)