Shape

I want these bags to carry plenty, but not feel heavy and clunky.   Here's some inspiration:

Tory Burch

Michael Kors

Miu Miu

Petunia Picklebottom

Ketti

Marni for H&M

And of course, there's always the simple rectangular tote.

Should the computer fit in horizontal? or vertical?

I've heard that it's hard to find things in tall vertical bags - so I'm leaning towards horizontal - at least for the first line.

What are your favorites?