You roasted the bones waaaaaaaaaaaaaaaay too long. Next time, try 20 minutes at 425F.
When I make chicken stock, I like to use one carcass worth of roasted bones to a whole chicken (which may be parted). I also like to add extra wing tips, feet, combs, and necks if they're available.
Start the carcass and raw chicken together. Simmer, and skim until it doesn't create any more scum. Remove the chicken pieces as soon as the meat is barely but completely poached. Meanwhile allow the carcass to continue to simmer.
Allow the the pieces to cool just enough to handle, strip them, discard the skin, reserve the meat for another purpose (pot pie, enciladas, etc.), and return the newly cleaned bones to the stock pot. Skim again if necessary, and add the aromatics and a bunch of parsley. If you're using other herbs as well, you may want to use them in the form of a bouquet garni.
If you keep the aromatics out of the pot until all of the scum is gone, it won't stick to them and cloud the stock as they cook. It's one of those little, important things people forget to tell you, that makes the difference between quality and average.
If desired, you may roast the aromatics until they develop some color before adding them. If you want to keep the stock's final color light, don't roast. If you want to keep it very light (a "blanc"), use parsnips instead of carrots.
Try and remember that stock is brewed more than it's cooked. Be gentle with the temperature. All you need is enough heat to extract the flavor from the ingredients. If it helps you to think of it as an infusion, do so. Don't be any rougher with it than you would be making tea for a lady.
Speaking of which, it's not "camp coffee" and you don't need egg shells. If you're going for ultimate clarity as for a consomme, you might well try an egg white raft, but that's a different thing.
After the aromatics and carcass have simmered to tastelessness, remove the bones, strain the vegetables out, and return the stock to the pot. If you like, you can press the mass of vegetables with the back of a spoon to get all of their essence into the pot.
Reduce the stock at a simmer until your desired concentration is reached. That should take about four to six hours from the time you first put the chicken and bones in the pot.
Either (a) allow the stock to cool settle and defat by skimming the top (repeatedly) with a spoon; or (b) chill and remove as much fat as you like when it solidifies. Stock cools much faster in several small vessels than in one big one.
Reserve all of the removed fat for another purpose, frying potato pancakes for instance.
Hope this helps,