Hihidaruma
It's a flaming daruma, people know what darumas are, and it's pre-evo kept it's name
'
koiking-
people know what koi are

upa/nuu-
the names seem to match the vacant expressions on their faces

Megayanma-
self explanatory

Majumbo-
funnier monster name than tangrowth

who do you think should have kept their name or had a different one?