Hi Lauren! First up have a look at these links if you haven't already.
This link shows you what other TPFers can carry in their bbags of respective sizes.
What's in your bbag
This link shows you how Firsts and Cities (and other styles) look on TPFers.
Photos wearing your bbags only
If you click this link, look for the threads on 'First' or 'City' to see many beautiful photos of Firsts only or Cities only.
Balenciaga Clubhouse
Having said all that, I'm 5'4 & I have a First and Twiggy. The First to me is very much a going-out purse as opposed to a daily. I can only fit my wallet (long one), cell phone, keyholder, small agenda and misc stuff eg mints, lipbalm etc. It doesn't look too small or too big on me at all. I can get the shoulder straps on my shoulder but it's not comfortable to carry like so, so I usually hand carry it or place it on my arm or use the longer strap on my shoulder.
Next up the Twiggy. It's deceptively roomy and is about as long as a City but shorter. I use my twiggy daily, I can fit whatever I put in my First plus a 14oz water bottle, light cardigan rolled up into a ball, pencil case, foldable brolly etc and more . I'm getting a City next as I'm planning on using it for A4 documents as well. I don't believe it would look too big .. I would even be prepared to buy a Work! More leather to love!
The other thing is, Violet is one of the more popular and versatile shades (to me at least). So if you've found a Violet First, know that it will get snapped up pretty soon!
Hope this helps!