I don’t have Dutch doors, but I do have a side barn door that goes right out. It makes life so easy - open doors and send horses out, close the gate or door depending on the season. Reverse to bring in.
For outside water I am spoiled by having an artesian well. It was overflowing the well casing so we added a fitting a few inches from the top and hooked up a 3/4" water line and ran that to a trough in the sacrifice area. I also had to add a nearby culvert to a natural drainage area for the trough overflow into. Based on how fast the trough fills when scrub it I estimate around 900 gallons a day goes through the trough and as long as the line doesn’t freeze (I reworked it this year after problems the last 2 winters) my trough doesn’t freeze due to the constant flow.
This year I put in a hay floor using rough cut 2x4s, 1x8s and 1x10s to replace the pallets I had been using in my storage area. It made stacking so much easier and it’s much safer to walk on.