Last I checked most mutations were up to date on the wiki.
Insanely Strong should indeed give you +7 strength. IIRC some mods make it bugged and give no boost at all, so it could be a mod you are running.
The +4 strength is likely from HUGE if you have it.
Also I’m well acquainted with most mutations, so if you have any more questions about mutations or mutants in general feel free to ask me 