I'm hoping to start addressing envelopes for my wedding soon, a couple a day over the course of a few weeks, since I have a lot to do and not much free time. I know I'm supposed to hand-write the addresses, and I plan to do that; however, for the purposes of this question, computer mock-ups were easier.

The addresses will be in the center of the envelope, with the return address on the back flap. However, should the text be centered or aligned left? I couldn't find any definitive answers, so I came up with 3 styles. What looks best? Left aligned is what I would normally do, but it looks off to me without the return address in the corner.
Thanks!
Style 1:

Style 2:
Style 3: