On Friday, June 5, 2020 at 8:59:21 AM UTC-6, wrote:

https://youtu.be/wwsa4PVYMJY

Excellent.

For an FES ground assist, you need enough energy for a rope break like return to the field when the FES does not work.

I there a safe and economical way to make a winch that can just get you to 300 feet?

Might be some minor issues with the design example in the video.

Good and cheap are mutually exclusive. A good, safe machine won't be cheap.