As an Eagle Scout, I remember how nerve-racking the EBOR was and I understand you're kinda freaked out. So I'll give you the following advice:
Merit badge sash - wear it! Not only does it look sharp, but it also provides a point of reference when they start asking about merit badges. Make sure all of your merit badges are on it.
Philmont belt and hanging patch - both are acceptable.
Pins - ditch 'em. If you're not sure if they're supposed to be there, they shouldn't. Your current service star, on the other hand, is a nice touch, and you should wear that.
New uniform shirt -