Appropriate layout for an address form

I've read a number of the questions both on here and elsewhere suggesting to avoid a two-column layout, lest you have to zig-zag with your eyes while filling it out and risk missing fields.

I'm working on a basic address form as part of a multi-step, and have opted for a single column, multiline layout. The challenge so far has been appropriate sizing of the fields while maintaining a fairly intuitive layout. What I have so far is this:

I'm not entirely satisfied with it, as I feel the Country drop-down is kind of "floating" about by itself, but the alternative was to simply have all fields exactly the same length:

Is one necessarily better than the other? Or is the form simple enough that really, it doesn't matter?