The way I see it you bought 55 lbs of feed for $10 and they threw in a free rooster with unknown provenance. ;)
He does look like some kind of production red so maybe he'll work out and make some good layers.
I started my current flock from free, unwanted chickens and after 3 years I've worn out...
If you want to develope a good flock I'd avoid the free craiglist roosters. There's no telling what kind of undesirable chicks they will produce. You're liable to raise up hens that lay a white 40 gr. bantam egg.
I'm not a chicken gene expert so I can't answer your question per se but to get the hens that lay the biggest eggs I hatch the biggest eggs. It takes many chickens & generations and much culling to acomplish this. With only a few random hens and 2 generations there's no telling what you're going...