Thanks for the feedback..
The icons on the left are "placeholder" graphics, and afaik are the only graphics (apart from the gunpowder barrels) that I haven't made myself, which is probably why they look a little "detached" from the rest of game.
At the moment I am wondering whether the "traditional fantasy" route is the best theme to go, or opt for something a bit different. I have a few ideas, but I want to clean up the code base, before embarking on a new direction.