The group pic is just weird, in my opinion. You are crouched down (makes you look short) and also you are all the way to the left. Seems like you squeezed in the photo than a group photo. My two cents

For the hookups part. I wouldn’t say anything. When you are conversing you could mention you are looking for something serious but not in a rush. I find this is the best way because you are looking for something serious (I guarantee if the perfect girl comes along you would lock her down) but you are also playing the field with the not in a rush. It also sets a foundation that they seek other mates if they want to be in a relationship yesterday.