To take
@Kaga-kun's thoughts to their logical conclusion, don't change your avatar until you've firmly implanted yourself into the minds of the populace. (Signatures are okay, though, usually.)
For example, I feel like the name
@Lawkheart used to mean something to me, a member I recognized. Then she changed her avatar and it was like a total reset, and I am forced to recreate her in my mental lexicon from scratch.
(Sorry Lawk, I'm working on it.)
That is why I have been using this avatar consistently across numerous sites for years. Ain't no way
I'm giving up on any progress I make!