Mine is pic related, the Victory Gundam. What I like about it is how modular the mobile suit is. It's the result of years of ms tech late into the Universal Century where now the Gundam is mass produced. In the show the rebel forces are shown to have a stockpile of Gundams in a bunker so they can burn through parts.
Honorable mention to the RX-79 G ground type Gundam from 8th MS Team.
Show
Im sorry that’s just a queen slaying in some heels, you can’t fool me, that isn’t a mech
Edit: I’m so sorry about my reactionary perspectives. Of course mechs can be queens that are slaying. I have done self crit