The oak trees might be a problem. Some members have put freshly-cut oak trees into their pond and suffered a fish kill. Others have done the same with no observable consequence.

The second problem is that it is very difficult to have a sunfish only pond! A female bluegill can lay 50,000 eggs during a single spawn, and she can spawn multiple times over the course of the year. By Year 2 or Year 3, you would need to be catching hundreds of bluegill every day. Otherwise your pond will be filled with skinny, stunted BG that don't grow much past 4-6".

Essentially all good BG catching/eating ponds also have a top predator to thin the huge population of small BG such that other BG have space and food to grow large. Frequently that predator is the largemouth bass, but there are other options.

There are lots of "stocking plan" experts on the forum. Hopefully, some will drop into your thread.

Congratulations on all of the work renovating your pond. It sounds like you have created great potential!

P.S. Which sunfish are you planning to stock? Bluegill, Redear Sunfish (maybe called shellcrackers in your area), or some of the wide variety of other species? If you add that to your post, then you will get some better advice.