I would initially just get some cheap hurdles and divide the space into two, and then after a while if they all get on fine outside just take the hurdle away (and you can always re-install it if necessary or need separate kidding space (for example when one goat kids the wether can still share with the girl not kidding etc). If they are all still quite young they should get on well. Pallets also work (and you will need them to build muck heap enclosures later on anyway...)
If you put in a central dividing hurdle you also only need one hayrack to start with, one of the panier style ones, you may even have one of you have an old horse place). I would advice against having hayracks at the back of the pens, you will always have to march through the muck to reach to re-fill them. Also make sure you have a kind of lid on the hayrack, otherwise they just pull all the hay out and use it as bedding... We just have bent some wire mesh into place and it swings open. Then enclosed with one of these rubber straps/bungees (and even those get eaten periodically.. or disappaer into the straw/bedding only to be found in compost several years later...). For feed bowls we use the cheap 1 pound-a-go ones from any supermarket, again we go through a few of them per year, but they can easily be washed out after cleaning out the milking machine.
My goats share pens in family groups, with one kept free for any individuals kidding, ill etc etc.