Meta-Ridley in Rosalina's dress? Haha. Never change Ridley thread, never change.
Though I would've liked a miniaturized version of Ridley better than Little Birdie in hindsight, it would've killed any element of surprise that there was with Ridley being cloned before progressing later in the game, and I prefer said clone retaining its memories of Samus, or at least like to think that Other Ridley had memories of her... And I don't like the idea of trying to hunt down an infant miniaturized Ridley that has no memories of you (who thus would not attack you). Would feel kinda cruel to me and would arguably make Samus no better than Ridley morally, or would've hardly been any different than if Samus had just outright killed the last Metroid on SR388 then and there instead of adopting it.
I dunno. Maybe your idea would work well if said Ridley clone doesn't get offed by a Metroid Queen later on while weakened because if that's not something you would change too, then a cloned Ridley's developed fear/hatred of Samus would only have been short-lived at best.