First one for sure. Your party, look your best.
Also, you mentioned that most of your friends will be wearing more of the rest, but that is no fun, to look like everyone else...With the first one you have the advantage of uniqueness... Soo there is more of the chance of "Wow, you look great! Where did you get that top from?" rather than "Hey I have the same top" or "I am wearing the same top" or "She is wearing the same top"
Buuuuuuttt noooooo....With you...it will be more like... I actually put thought into what I should wear and not look to similar with m guest.....Aaaaaaah...nice.
By the way, pretty.