Whatever you decide... Keep it simple, but make it something you know, not just something you read. It should comply with your policies, but not necessarily come from the IFSTA book or department policy .
Assessors know when you're trying to dazzle them with BS. That's a sure sign you don't really know what you're doing, so practice you're presentation, especially for time limits, and make it a topic you know.
Prepare several presentation and don't show you're "oh shit" face if you walk in and the assessors throw you a left handed metric gooble wrench and say "teach me this."
If it makes you feel better, I did a 10 minute teach-back presentation for a job as a HazMat instructor once. I did it on the uses of a wooden door chock and it got me the job.
Relax, put on your game face, and get yourself promoted.