I strongly agree. The Sam Browne belt always seemed like an afterthought to me. It didn't seem as though it was designed together with the rest of the costume. To an extent, that makes sense story wise as the bodice and boots were presumably some kind of artefact (e.g. perhaps Athena's amour) stored in the Amazon's armoury whereas I don't think the belt was from there and was probably a late addition by Diana when she left Themyscira.
But, I definitely didn't like seeing Diana's iconic "WW / Eagle" breastplate partially obscured by the belt straps.
Perhaps the rumoured "battle armour" will provide Diana with a more integrated way to carry her sword and shield (which she would presumably be using against a foe which she thinks warrants upgraded / additional armour).