He is lovely and I can't wait to meet him. *whispers to myself: it is only another month, you can do it!*
Pink, I remember you talking about the mud in front of your barn before, now I can see the issue and I wonder how you manage in the winter.
If I may suggest, I'd build something like a pole-roof to extend over their stall entrances and allow for rain/snow-free access. You could also kind of "mare motel" it by fencing along the sides and having a gate at the end of the lean-to roof for each stall section. Then even on days they'd need to be up, they could still access a little bit outdoors of their stall w/out a huge muddy or snowy mess, other than a pee spot. I'd also modify the fencing to attach to their stall runs so you could allow them free-access as they wish during the day - but I'm all about making things easy and my climate is very different from what you have to deal with.