Did you use the Adobe CC Cleaner tool when you uninstalled? If not, the files that typically cause this sort of thing weren't removed, and were used again on re-installation.
I recommend using this to do the complete job of uninstall & cleaning, though the included instructions say uninstall with the OS tool first. It's worked much better for me when I do everything with this.
will it remove any plugins?
Not if they're installed elsewhere, outside of the Program file location ... what it does is completely remove all the preference & startup files for the app in question beside the program file stuff. Which does mean that if say you've got custom keyboard shorts or something like that saved, maybe custom workspaces, it's good to find the old preferfences file (oft in something like "User/appdata/roaming/Adobe" or something like that), and rename the folder prior to running the uninstaller.
If you can find that folder, you might just rename it with AfterEffects closed, re-start Ae, and see if it works better. If not ... do a full kill the beast routine.
Are you still crashing since the update? Please let us know.