You are quite good at drawing horses. It looks like you are doing well drawing them in considerable detail...
for the dragons, I'll pass on something Ive heard and observed being repeated by many dragon artists in the kin community, and that I have seen in many technique books. many artists use equestrian anatomy for a base when drawing dragons. Lengthening it here, shortening it there, smoothing and stretching it slightly and making the lines more serpentine and streamlined; adding talons or paws in place of hooves. as horses have a majestic gracefully powerful form. that can still be visually violent, at least in terms of angles in the body) when in motion.
My tip on drawing any fantasy creature from dragons to monsters to creepy-crawlies, is to look at thee things/creatures in the world around you. and to not become too relient on just one sort of form. everything you need for any fantasy beast can be found there no matter how twisted or grotesque or fierce it seems
your wing membranes are looking good though
but then what composes a "dragon" is up for the artist to discern.
Keep up the hard work, though your doing fine.