Board Thread:Support Requests - Getting Technical/@comment-4356266-20150828150639/@comment-5558012-20150828154442

Not exactly what you are asking, but you could limit the number of images per user by creating two galleries each and using the  class as done here to collapse one by default. This'll keep each section approximately the same height and allow for it to be expanded.

There's also the New Image Galleries, but are less ideal unless you don't mind all images being cropped.