One of the big problems regionally is the quality of spotter training. There is a tendency to show pictures of pretty/perfect supercells in a flat treeless terrain taken from the plains. If you train your spotters with these type images then that is what they're going to expect to see when spotting in the field. Obviously, this isn't realistic in the Southeast. Storm spotting here is a dirty job, no doubt, and is much different than the plains and portions of the Midwest. Fortunately, the Nashville office as well as a few other NWS offices in our region have worked hard to add images obtained by local spotters/chasers to their spotter training presentations. Even though they might not be the picture-perfect supercell with a well-defined wall cloud, they are a more realistic demonstration of what a local storm spotter might see and illustrates just how much more difficult storm spotting in the Southeast really is. My first suggestion would be to place an emphasis on this in any supplemental training that you provide for your group.
There has been a movement in some local groups toward focusing on quick collection and dissemination of post-event damage information. Through the use of tools, technology, and techniques, these groups will target specific areas of their county that storms have just impacted and proactively search for damage. This is very useful information! The quicker the reports of damage can be received by meteorologists at the National Weather Service and by state and local emergency response officials, the better. Focusing on this, including the development of a methodology for doing so that works well in your county and for your particular group, would be my second suggestion.
A third suggestion would be to talk to your group members and ask them what they think their weaknesses are, and what areas they would like to see more training in. There are bound to be certain things that the spotters of your group feel uncomfortable with. You could then focus any supplemental training on those areas, too.