Starting chicks in paddock system

I am thinking about putting in a small paddock for a small flock of chickens or quail. I had a small ranch growing up, and we had chickens off and on, but we never tried anything beyond coop/run, so I am basically brand new to this( and I didn't care as a kid, it was just another chore I had to do, so I didn't pay much attention to details) I love eggs, and as long as my cholesterol doesn't go up(which I am not convinced eggs will do anyway) , I can and will eat them every morning if they are free and available. I have about 5000 sq ft of backyard, about 1000-1500 is slowly becoming my garden, so I have about 2500-3500 that would be available for paddock. I hunt, and thoroughly enjoy quail as a meat bird, and I assume the eggs would eat as well as chickens, just smaller. I had neighbors who had chickens (stuck in suburbia for now) and hated their stupid rooster who would start singing at 4am, so I dont want to put that on my new neighbors that I like (though he is a chef, and would probably like a basket of eggs now and then to go with the squash and corn he usually gets in the summer) so a rooster is not an option. I was thinkin about just buying a few chick hens, maybe 3, each year or so, and rotating them as layers and meat birds. If I did quail, I could get away with havings cocks, thus fertile eggs, and hatching a  couple chicks to make up for the roasters. How many of either could I reasonably raise with a 2500 sq ft paddock?
Also, I have been reading conventional wisdom as to starting chicks, but this doesn't seem to jive with Pauls view on the low maintenance paddock shift system. Is all the careful feeding and such necessary? Will they do okay if I just toss them in a paddock full of grasses and clover?  I live in CAs central valley, and I have temps from a occassional 25* to about 110* in the summer. What precautions do I need to take for each species as far as weather?  Also, any breed recommendations for meat/egg use?

While many worry about chickens in cold weather, I worry more with hot weather.  Chickens can do quite well below 0° F, but as temps soar above 90° they need a shady spot to hang out.  In hot weather, they will go off of their feed (which translates to fewer eggs).  Hot weather kills many more chickens than cold weather does.  Chickens neither sweat, nor urinate...they eliminate excess heat/moisture through their lungs, which can lead to many problems in hot/humid weather.  Ample shade, and maybe a cheap box fan for those scorching days will yield healthier birds (and more eggs).

john is right.  i wouldnt worry about cold.  but its the heat..............another trick that some good chicken men use that live in intolerably hot conditions is they will take a water hose and water down the dusting areas or bare dirt areas that chickens need for bathing.  ive even turned the hose on real light mist and mist the birds down.  they seem to tolerate it.  but to cool a chiicken down its best to have their feet wet and put water on their vent areas.  you can help them more by clipping the feathers all around their vents  down to the bare skin.  they can put off alot of heat in this area.  so no insulation their,,,more heat released.

darker colored fowl can generally tolerate less sun than lighter color or traditional reds.  so keep that in mind when choosing a breed.

i dont particularly believe in a dual purpose chicken.  but i believe in specialized for optimal performance.  red sexlink or goldens for egg production.  the infamous cornish X for meat.  i can personally vouch for the sex link and their ability to outlay most any of your traditional breeds. plus they are calm, tame and easy going.

i personallly enjoyed eating quail. but their eggs did not tempt my palate.  a different texture..  i  feel it would be harder to contain quail in a paddock system than it would chickens.

My favorites right now are Delaware chickens, possibly the strongest dual purpose breed. They were recognized as a breed in 1940 made from the Rhode Island Red and Barred Rock. The Delaware is practically just as good as those two in laying, foraging, and hardiness, but the Delaware is a far superior broiler. If you cross a Delaware back to either a RIR or a Barred Rock, the offspring are sex-linked color hybrids.

I'm not opposed to hybrids. But, if you depend on buying new hybrid genetics every year from a large coroporation, how can you call yourself sustainable?

In a 50ft x 50ft (2500sqft) you can probably feed 1 chicken in grass. However if you got 4 everybearing 20ft mulbery trees with seaberry understory(they have lost of bugs and fruits stay on the tree into the winter). Maybe add some winter squash that you open for them in the winter. dwarf dwarf mulberry leaves are also high in protein and chickens like them. They will also eat manure worms fed by the cow.

A little off topic but also take alook at this for ideas
http://www.gardenpool.org