I highly recommend boers! We now have 7 girls and a billy, having started off with two female kids a few years ago. We will for sure build up to about 12 to 15 girls (if the goat gods are willing and we get enough nice female kids

).
We have always had sheep and had wanted goats for some time but they are a bit more work so we needed to find the right moment. That may be a bit unfair, it's not so much more work as a different setup... fencing, shelters, foot trimming etc etc once you get in the swing of it it's actually pretty easy and I really enjoy it! The 40 or so ewes do take up less time on a day to day basis though... say 15 mins for sheep and 40 mins for goats.
Because of possible parasite issues we do not keep our sheep and goats together although I know some ppl do with no problems, we are fortunate to have the space so chose not to.
We keep them in with an 80 cm stock fence and a two lines of electric. One line 10 cm above the stock fence and one set just in front of the fence at about nose height. The only time they escaped was when we had a big storm and a branch fell on the fence so shorted the electric. They really are like no other goats I have had contact with (pygmys and several dairy breeds). Like all goats they are very intelligent but they are also extremely docile and generally easy and "well behaved". Ours have two open field shelters and are let out daily to pasture (we are in South America so don't get the rain we used to get in the UK). We still supplement with hay and plus give a small amount of oats at bedtime. Mainly because as with every animal (including humans) routine helps and this way they just put themselves to bed. Don't overfeed though as they will get porky!
We have had two males so far and both have been safe despite their colossal size. Same safety rules apply as with rams and other billies. We change bloodlines with a couple of local breeders so we can keep our girls back for replacements. Many here aim to have three kiddings in two years, we do not do this. One kidding per year is fine and kinder to the girls in my opinion (not judging anyone else though). Does are bread for the fisrt time at 8 months subject to being up to weight and continue to grow well. In fact the girls we have homebred have grown bigger than their mothers who we purchased. So as long as their nutrition is good you won't have any issues (a bit like breeding ewe lambs which we also do).
As for where to sell, it would be a case of doing a bit of research in your area. I used to live in Dorset and still have farming friends there. Mainly sheep but a couple have goats, but they all say they could easily sell direct to local butchers as the demand is there for good quality goat meat... As for here the demand is very high so the future looks bright for our Boers.
I love all goats, always have. I would like to add a couple of dairy goats for home milk consumption but the quality here is quite poor. So for now I will not be getting any but the Boers are great! Highly recommend them.
Good luck!