I'm going to echo a lot of the same sentiments already posted:
1. I wouldn't shoot this at f13. In fact, I'd go for a much narrow DoF in order to get some blur of the background. And that narrower DoF may have helped create a photo that didn't feel as flat.
2. Definitely get 'em all closer together You're not seating them for a party but a temporary picture where people are expected to get cozy and be closer.
3. I'd move them away from the wall. To me, having the way in focus is a distraction. The shadows on the wall are a distraction so moving away from the wall gives you a chance to minimize those.
4. Very good job of getting everyone cooperating at the same time--there isn't one person in the photo who is blinking, grimacing, looking away, or distracted--good for you.
5. I've got no problem with lambie in the photo, it could potentially add a nice and personal touch if it's facing the camera. In fact, when I'm shooting group photos with kids, I'll often get cooperation by announcing that we will have one designated "crazy face" photo where everyone (including adults) has to make a silly face....but until then everyone cooperates. Did another group photo where the kids wouldn't let go of their stuffed animals so instead I had everyone holding one (which got the kids to stop having tantrums, they passed out a specific animal to each parent, everyone had a happy face for the pose). The balloons are a nice whimsical touch that adds color
6. One easy way to get a tighter grouping....the woman on the far right (photographer's right), I'd have her standing in back so even if you can't get people closer together, at least you get a tighter grouping. And with a tighter grouping you'd be able to eliminate that shelf of tchotkes on the shooters far left.