As a rather active member of the Taiko Community. I can tell you Taikonator 3000 is deeply loved.
The entire concept kinda speaks to how many people react to Taiko players thinking that we must be robots or something. So Taikonator is the best mascot as it perfectly reflects that attitude of being a robot by other players.
Yea, as the T3000 is more likely to SS taiko maps
But it would be really great to have all mascots represented by people
(Btw maria won't show when I play osu!mania)
Taikonator is already the perfect shape to replace Pippi-don. Combobursts are directly tied into the Don character and not a character popping up on the screen like in the other gamemodes. So a human doesn't work as well for Taiko simply for this simple fact as you have to make the human look like a don
You don't have to have the mascot pop up
She can stay where pippidon is now and pop up every 100 combo or something
You don't need to make the human like a don, that's where you are wrong