Ok, a couple of options spring to mind. Cowgirl, him ontop is really classic for pegging. So is missionarry (works best if you shove a cushion under his bum). As you said, Legs in air options also classic
There is a humungous list of positions of the week somewhere, give me a sec and i’ll go find it
Here we go. Should give you some ideas. if you go into the options, they all have a non-hetero bit at the bottom that usually tells you if its good for strap-ons, anal etc.
Hopefully it gives you a few fun options
Spooning and the one that looks like doggie but where your both on your sides (cant think of name) might work well
Ps. Over the moon for you both. Hope you have a blast 
Hard press looks like a good option btw 