I have an old farm pond in North Carolina with bass and bluegill. There are plenty of small bass, but only the occasional monster. As a tournament bass fisherman, I only get excited about fish over 2.5 lbs. I have occasionally brought fish from the lakes (if they are over 3lbs and healthy looking) but when caught again, many of them look thin. Please help. I do not want to do anything that will hurt the fishing. Some of my actions and questions are as follows.

1. The water is somewhat clear, should I consider fertilizing?
2. I have trapped a few crawfish and chubs from creeks and put them in there. A local baitshop has "shiners" but was unsure if they were golden shiners. Would stocking shiners help, or could they "take over" the pond? I've heard that fathead minnows in an existing pond are almost useless.
3. I made a couple of structures to put in there, since the fish have very few obstacles as ambush points.
4. I know that I should harvest some small bass, but I hate doing that. I will if it is imperative.

Any help would be greatly appreciated.