I’d like to see the ship tree updated to have the ships that are currently not listed in it. I can’t think of a reason to not have all of the ships in the game listed.
Society of Conscious Thought - Sunesis, Gnosis, Praxis, etc.
Concord - pacifier, Enforcer, Marshall
Special ships that are out there (ie The Fiend)
TL;DR: If you can build it, buy it, or receive it, get in it and pilot it, it should be in the ship tree.
For us newer kids in EVE. Could you define the acronym ISIS that you mention in the title? Because with recent events the context can be very helpful. I am also just pretty curious.
The ship tree in Eve Online used to be called ISIS. When the terrorist group started beheading people on the internet, CCP issued a release where they dumped the name ISIS.