Will changing your Apple ID password affect a pending remote erase request?
Changing your AppleID password is an excellent idea, but you want to place your iPhone into LOST MODE rather than to erase it:
https://support.apple.com/en-us/HT201472

Here is an excellent article on choosing a password, from Carnegie Mellon School of Computer Science:  https://www.cs.cmu.edu/~help/security/choosing_passwords.html

I have read quite a few articles concerning stolen iPhones.  Many experienced thieves start by putting the iPhone into Recovery Mode, which erases all the data, and makes it virtually impossible to locate by you or the authorities.  Once in Recovery Mode, the only way to reload iOS (and reactivate the phone) is with the correct AppleID and password of the registered owner (you).

Odds are you'll never see your iPhone again, and some schmuck will buy it, only to discover it's unusable.