Designing a small permaculture grid – fruit, herbs and flowers on a suburban lot

I’ve been reading about permaculture and want to convert a corner of my yard into a permaculture guild. My idea is a dwarf pear (or some kind of fruit tree that would do ok in zone 8a) surrounded by nitrogen‑fixing clover, yarrow, and comfrey for mulch.

To plan it out, I sketched the area out on paper. I am hesitating though on pulling the trigger – do you guys have any go-to resources on designing a guild? Something that lets me put together combinations of plants and my space and it would help me think through them and make suggestions.

For those practising permaculture: what have you planted under your fruit trees? Are there any groundcovers or herbs you’ve found especially beneficial? I’d love to hear about your guild setups and any pitfalls to avoid.