Ooh this is a tough one! I really love the first or third one, but leaning more towards the third one. 😍 Have you seen the Drew in person? The small size is actually bigger than the name suggests. It holds quite a bit. The mini is smaller and perfect for carrying essentials. Looking at
farfetch, the mini is width: 20 centimetres, depth: 6.5 centimetres, height: 16 centimetres, strap: 55.5 centimetres. The small is height: 20 centimetres, width: 23.5 centimetres, depth: 8 centimetres, handle: 53 centimetres. I would suggest looking at mod pics for size! I have the mini because I like my bags to be proportionate to me, and I typically don't carry much. For reference, I'm 5'3.
The Drew comes in 4 sizes (from smallest to biggest): nano, mini, small, and medium. The medium is easy to tell because it is ginormous and has a leather strap attached to the chains. I hope this helps a little!