Congrats on the new pond!

None of your thinking is out of line. However, it may not yield you the optimal results.

I very much like that your pond is full. I don't like that the source of the water is not obvious.

A 15' tall dam usually means that your pond was constructed in a slight valley and is filled with surface run-off water. Are you sure that the pond only has 1 acre of watershed? That should NOT be enough area for your level of rainfall west of DFW. Maybe go out as the next rainstorm is tailing off (no lightning) and observe your pond. If it is filled by surface run off, then water may start flowing through your outlet within a few hours of the storm.

If it is a groundwater pond, then it can't be filled on top of a hill, unless there is a significant amount of higher ground surrounding your property.

Most of the new pond owners that come here are very reluctant to kill the fish in their pond and start over. However, most of the pond management guys recommend that exact strategy when someone wants to invest time and money stocking a pond to meet they desired goals.

However, IMO it is too early for you to confront that decision right now.

I say keep on fishing. Try different times of day, weather conditions, and baits.

Are you fairly handy? If so, then read some of the threads on fish traps. If you built 2 or 3 fish traps, you could certainly perform better sampling of your pond.

Hope you have fun on your new pond journey that you are just starting.