I plan to dig out some of the ground next spring, edge and fill it in
with rock. Not sure if we'll do that to both sides. Muddiest area
seems to be between the house and shed.

I am still going to do this just to keep it cleaner. All the leaves in
the surrounding 200ft radius seem to end up here. Add mud to that and
you have a pain in the a%& to get leaves out along with muck. So it
was planned for based on more than the shed issues.

Install a perforated 4" PVC drain pipe within the rock/gravel. This
reduces the amount of gravel your trench requires (& reduces cost
for gravel). This French drain system should help along your homes
foundation, also. Continue with the (solid) pipe (or some flex pipe)
away from your foundation, if possible.
Sonny

I've done the french drain once a long time ago back east. Used it for
a couple things and it worked well enough in an area with a high water
table, clay base and sandy soil.

I was thinking to try that here but the previous person threw down
some concrete (originally there was an old deck there) and I really
don't want to try and hammer that out. So I will have to look (in
spring) to see if any under drain is possible. If so, I will.

Train your mind to test every thought, ideology,
train of reasoning, and claim to truth.