New Coop- flooring questions & food placement

Hi- We have a new coop and are trying to get it set up well. We live in Seattle, so it is wet much of the year and are drying to avoid a wet run and muddy penned in area. And rats, racoons and possums are potential problems.

Since the photo was taken I have installed a brick-lie patio that is larger than the coop/run by about 6-8 inches on all sides and the coop/run is now placed on top of that. We did this to help it be easier to clean and prevent rodents from tunneling in to run area.

Here is the coop:


Our general plan is to build a larger "aviary/pen" around it allowing them more space to run around in the dirt, etc and is covered with at least a wire mesh to protect from raccoons. Something large enough that we can walk to enter.

We are wondering:
1). How much overhead rain protection should we have (given how much rain we get)? Concerns are mud and wet bedding/shavings in run.
2). What can we put on top of the bare soil that will prevent a mud pit in the uncovered areas and that the chickens will like? There is currently playground/wood chips in place but we were going to move them. We want them to have space to dig in the dirt and dust bath etc.
3). Would you locate the food hanging from under the coop if the base of the run was secure from rodents? Or must it be in the coop itself?

Thanks!