Females can be housed together for the most part, but there is always the possibility of fighting or one picking on the other so it's good to have a back-up plan. I totally agree though, wait until you know if your Beardie's a boy or a girl before you get another one. They can be quite social, both with their humans and with each other. My two girls take turns eating from their dish and like to do everything together, and most of all they love teasing my male when he can see them. Drives him nutty, but it's adorable how they team up on him. :lol:
It really depends on the personality of your Beardie. Some really enjoy their personal space, others prefer to have company. And scratching on the glass is perfectly normal. Some people might think your enclosure is too small and that's why they do that, but I think they do it no matter what their enclosure is like. (Not that I recommend you keep yours in a small enclosure; they're very active and need some exercise room). They just want to get out and see what's going on, that's probably why they scratch the glass. Very curious little creatures, they are.
Some dragons will play with toys, I've heard. Although mine seem content to ride around the house on my shoulder and explore my bedroom, conquering piles of blankets and clothes, and my male loves going for car rides.
Bath time is a pretty fun time for them. They love to soak in warm water, and some even like to swim. Your baby will enjoy all these things more as he gets bigger. Right now his primary activities are probably going to be eating and pooping and exploring all the cute little things he can do, like head bobbing and waving and jumping and climbing. Each dragon has their own very unique personality; you'll get to know yours soon enough. They're awesome pets as long as you take good care of them.
Have you checked out all the care sheets and such? They're a huge help getting your setup together and establishing a healthy routine. If you have any questions, we're here to help! But I'll warn you, check out those care sheets before you ask because a lot of what you need to know is already in there.