Good tips so far. I'll add a couple more...
1. Certain species of fish like crappies and walleye tend to suspend in the water column when they are feeding - especially after dark. If you have electronics they should be easy to identify. If not, start jigging about 2 feet under the ice and then drop your jig another foot or two every few minutes until you find the right depth. Once you find the depth, mark it on your line and go back to that same depth. When fish are suspended, and feeding, they will often hit a bait that is three feet above them but won't hit a bait that is six inches below them becuase they simply can't see it.
2. Can't decide which bait to use? Why not use both? In PA, you can jig more than one bait at a time while ice fishing. This allows you to see which bait the fish want and also gives you a chance to catch multiple fish at once. I will do this when I am fishing crappies and other panfish. I typically will tie one jig and leave a 10-12" tag end and then tie a second jig to the end of the tag. I personally like to use a small, heavy jig on the bottom and a larger but lighter bait above it. If you use a heavier jig on top, it tend to tangle the line because the heavier bait drops below the lighter one. Just be careful when you are bringing a fish through the hole. The hook that doesnt have a fish will sometimes get stuck at the bottom of the hole and can prevent you from landing the fish so just be gentle when you land them.