I was looking at fastboot -h and saw the different functions there. I initially got curious when I saw some of the functions you were using. I saw that erase function and was going to use it myself for my Shamu if I couldn't get the normal flash over Bliss ROM to work, because no matter what anyone says, TWRP is buggy AF. I never remember having issues before with previous devices, but it has screwed things up more than once with both devices here.
Hell, I might still write up my own little batch file for use with wiping my devices anyway.
But, yeah, it lets you do a lot more than just fastboot boot and fastboot reboot. lol.
You've only seen the beginning of what I have planned. The refactoring was necessary to support what I intend to do next to make this thing a LOT more robust and useful. The device auto selection is just a taste of what's to come. And yes, I also modified it to auto select the latest android version and latest image, as well. Remember...I said mind reading.