I can agree here
resigning mid game
Whatever you do, don't just leave the game without resigning. I've had opponents make me wait up to 8 minutes after they lose their queen for the game to time them out, maybe hoping I'll offer a draw instead of waiting, or that maybe I'll just resign.

I once won a game where I lost a queen. My opponent made a plan, and he took my queen with a horse and a queen. Then, I designed a similar attack and took back the queen.
Resigning in a lost position isn't bad etiquette. Playing on in a bad position isn't bad etiquette either. Some people need to stop being so sensitive, either is fine. The only thing that is bad etiquette is abandoning a game in a losing position and timing out with no intention of playing on.