you do NOT!! have to apologize for the “crap renders and materials”… You’re working on something man! You’re growing, and here to get feedback for it. Not to wow us with the latest and greatest most epic piece of art ever. So whatever you do, KEEP GOING!
There are a lot of ways you can improve on this, and most, if not all of them boil down to anatomy. Let’s make an easy example: the arms/wings. Dragons haul a massive amount of weight, they need strong wings/arms to carry them. Their wings look like a bat wing, so look up references for bat wings. In your current dragon, you have a blob for a shoulder and some blob sticking out which sits between the “upperarm” and the “shoulder”. For starters, model/sculpt a normal arm, until you get to the hand, then instead of a hand, make each of the fingers much longer and that’s where the tissue for the wing will be. Again, look at bats for reference.
Your dragon also lacks definition in the torso on all areas. You have no defined chest/torso muscles, the abdomen (stomach region) is messy and the back’s most apparent flaws are the lack of a spine column carrying the creature and shoulder blades with muscles.
What you could do is look for some reference photos of male muscular models, study the anatomy and even use them as background images (front view and back view) to get the definition you’re looking for.
As for the position for rigging and animating… In my humble opinion the best position is usually something neutral, between all neutral poses. In humans that means the knees slightly bend, legs straight under the body, back arched a tiny bit but not much, and the arms not in “T” pose but in “Arrow Up” pose. In a dragon… well, a dragon would have 4 legs and 2 wings, so I’d look at a monitor lizard (komodo dragon) or in this case, Wyvern thingy (2 legs, 2 arms/wings) More like a dinosaur. Strap some (counter)weight to your butt (tail) and lean forward like you’re a velociraptor or something. Look up reference images, and play with it a bit until you have something that works for you.
Learn some more anatomy. It will greatly enhance any sculpture you will ever make.
Don’t let this criticism turn you off. By modeling this in the first place you’ve already come far. Keep improving!