To me, it sounds like you are looking to be talked INTO it. So here goes...
GO FOR IT!!!! You will not likely keep your original set-up exactly the way you plan it right now, anyways. You will have to HAVE the goats before you know what will work. You will fiddle with things until it works for you.
Yes, it is muddy now, but it is not muddy year-round. Put the road base in, and have a stack of pallets to put out in the really bad parts of the year. I actually make a row of "stepping stones" for my goats when it is really muddy in the area right next to the barn. The straw and poop and hay builds up between layers of snow and ice, and it is impossible to clean up until late spring and becomes slimy mud in the meantime. I don't want their feet in that much, and they hate it enough to use my stepping stones (the plastic blocks I mentioned on byh.) You can use pallets, cinder blocks, homemade platforms from scrap wood, stumps....goats love to climb, so as long as what you use is stable and does not have holes big enough to trap a foot or leg (close up the spaces on the pallets with more boards from more pallets....) they WILL use them.
You can sell does in milk in a heartbeat. You can even pre-sell the kids. Yes, some will go for meat. That is not unreasonable, and you will get more used to the idea. You do not have to eat them yourself and then consider yourself a ss failure if you can't. I am so relieved to have sold my buck (today!) because he was going to freezer camp next week if they didn't pick him up.
If one doe kicks another out, you can sell one of them...either the alpha or the low one, whoever you like the least. Like horses, there will always be an alpha and some tussles. My first two pairs of goats got along great and were/are inseperable. My trouble began when I added Ginger to the mix, a very young doeling with no mama to protect her and give her a place in the herd. I will be producing my own, so that will change. Hopefully. If not, Mya moves on to a new home. She has greater value now that she is healthy and is a very experienced milker. You will create the same in your does. They will have enough value to be sold to good homes.
Like everything, it will seem complicated at first and every task will take too long. Then before you know it, you will be doing everything by habit, without really thinking about it. Milking is very meditative and soothing for the milkmaid. So it is worth $200 per hour, the going rate of psychotherapy!!!
Does that help? Good luck and have fun! I know you will, even if you decide later to sell them. You can break even, you know. So the experience will be worth it even if you decide against it. If you milk for even part of a season, you will be ahead of the game finacially. That milk has great value, as do the products you can make from it. Fresh, raw milk is more than a condiment. It has tremendous food value and healing powers. I know this firsthand, and it is very apparent to me now that I have been a couple of weeks without fresh milk. My IBS is returning, even with raw frozen milk. Even if this is not an issue, it illustrates what a wonderful thing raw goat's milk is.