Is dressage still fun?
thank you for sharing the photos. Looks like you were having some fun. Was that a test? Looked like a "judge bow" at the end.
The horse has quite a belly and is a bit swayed back so this makes it harder for you to keep your leg down under you. The saddle looks like it is a bit high in front (due to the horses shape, no doubt) and this puts you automatically into a bit of a chair seat; you lean forward in the upper body and are forced to put your lower leg forward to counteract the shift of center of balance forward. Could a slight wedge pad help, perhaps?
YOu look like a very kind rider and that horse is very happy with you. I love to see that, even if the horse IS lacking a contact to follow and has like ZERO impulsion. But heck, better to start that way then to start all serious and heavy and driving. You'll start picking up that contact, getting your leg down (lower your stirrups ONE notch as soon as you feel comfortable) and letting you pelvis find a nuetral, more vertical position (it is very rolled forward ala hunter.
Also, knit picking, I know, but don't look so far into the circle when you are in dressage. IT's a dead give away for an ex hunter rider!
Look between your horse's ears, or to inside ear, no further.
Cheers, dear rider.