I am going to jump in on a couple things in the middle of the night while the dog takes a leak.
If you are talking about that pen mandrel being used for call making, skip it. Don't think twice about a pen mandrel for call making. If you are willing to buy all these other tools, it would be the weakest tool in your shop for making calls.
On your drill bits, look to buy Silver and Deming type bits, also called reduced shank bits. They will allow you to drill 5/8", 3/4", and 7/8" for example.....with a 1/2" shank on the bit.
I like having the collet chuck and using it to hold my straight shank mandrels.
You are getting a good list going. Keep asking questions and tinkering!