Millington said she was concerned that some of the gallery’s artistic heritage was no longer being given the prominence it deserved.
“The round room, which is when you first come in, it’s architecture is glorious and I feel like the current curation in there doesn’t quite match the space.
“It used to be jam-packed with academic paintings, old masters, pictures of Greek gods being pulled along in their carriages, and it was a place of absolute wonder.
“The walls now are white, and the pictures have been hung in a color-coded arrangement, which just seems to be a bit gimmicky and lacking vision.”
Sara Wajid, co chief executive of Birmingham Museums Trust said visitor numbers had increased since the re-opening and that the museum was working to make its collections accessible to a broader audience.
“The museum isn’t only for highly educated art historians, and the truth is we have to do a lot of different things.
“By putting on the Ozzy Osborne working class hero show, we have attracted more visitors than ever, in particular people who’ve never been to the museum before.
“We should be cultural leaders who are working for the people of Birmingham to get them the best they deserve,” she said.