Thanks, guys. You've persuaded me to leave the wood uncut and hire a specialist to reconfigure the faucet's location, angle, and so on.
I live in Maryland. The plastic U attachment is probably 15 years old.
If you hire it done tell them you want a quarter turn valve. Not only do they hold up better they are much easier to open and close than the gate valve type like you have that take several full turns to operate.
The freeze proof type come in both types.
Also keep in mind the freeze proof valves only work if there is nothing attached to them over the winter. Even the quick connect adapters will hold water with the valve off and will cause the outside part to freeze and break. Don’t ask me how I know this.
As to removing more wood to make it a little easier to get down there open and shut the valve if you end up doing something like I showed above. In your photo the chunk of wood to the right against the brick isn’t doing anything as far as I can see and one wack with a chisel from below would knock that off and give you double the hand room. It will still be tight trying to remove the jumper hose but if you removed it from the higher valve like I have in the fall and let it fall under the deck it would drain without taking it off down there. In the spring just pull the short hose back up and connect it and turn the new valve a quarter turn.
If you have a basement then you could get away without any of this messing around and rig it down there to have a shut off and then a Tee with a drain valve with a bucket to catch the little water going out the wall. They were done that way for years and you may already have that setup in the basement.
No one older wants to get on their knees and reach down in a hole every time they want to use the water. When I was doing mine I was thinking the whole time I’m spending 4 hours adding an outside faucet and all this to save a few minutes every other day watering some plants. Now that it is done it is funny how some of the simplest of things makes life that much easier and I’m glad I did it and now have it right forever.