Would GirlDM suit Momo or May more?
Are we talking about casting the characters in live action? Because new May needs to be played by a tall bombshell with an obnoxious attitude, while previously May would have to have been played by someone more petite with an obnoxious attitude. Could be tricky finding a matched set of actresses if you wanted to cover the transition.
Bubbles would of course be the biggest challenge. Some special effects would be unavoidable.