Get rid of the Train button and just use the Build button. The menu that pops up could have tabs on the side (like the spellbook does now) for buildings and units.
Tabs are a good idea, though a little redundant since the build menu isn't up all the time and would just put one extra click on getting into the "train units" section.
but what is the point of replacing the text on the train button with "Build"?
("Im sorry, Imma go build one piece of militia in my shed, be back later?" (meant as a joke, so don't take that too personally).)
Not trying to be mean, just can't figure out why 
I do like the new UI too though!
Sincerely
~ Kongdej
