Those are all excellent measures.

Especially the trees because they will drink a spring dry and the roots can disrupt the spring heads and cause rocks to shift.

What you want is a 'silt trap' (settling pool) that can filter some of the larger stuff either before your reservoir or after it before it goes to the turbine(s).

In the reservoir itself you want to create a spillway (standpipe) out of your big main output pipe. Like this one or similar:

You want to draw the water from anywhere in the 'Good water quality' area. I shoot for about three-six inches above the 'Poor water quality' level so that even during a drought the standpipe is still functional.

The left side of the 'T' at the bottom of the standpipe can have a removable cap for draining the reservoir.

Source: extension.msstate.edu/content/designing-the-dam

Gotta rack my brain on the turbines but take a look here for now: https://www.powerspout.com/ There are really good calculators there and they have guidelines for various turbine styles depending on your terrain, volume, flow etc.

Glad to be of assistance! I love seeing this project progress!