FreeCAD is a start, but nowhere as good as AutoCAD, unfortunately. I haven't tried GIMP's v3.0 version yet, but 2.x is terrible to use. Depending on what you need to do, Krita would be a better alternative.
Word alternative: I started trying out OnlyOffice, based in Latvia. So far it seems decent. Definitely doesn't look as dated as Open- and LibreOffice.
Logic, FL Studio alternative: Audacity is in my opinion not a serious alternative. If you want simple voice overs, sure, but otherwise no. I'd recommend Reaper instead. Not open source, but there aren't many DAWs that are (maybe Ardour, but I don't have experience with it ). Reaper is really open as far as proprietary DAWs go.
The best alternative to commercial CAD systems is commercial CAD systems if you know what I mean. That said, FreeCAD is the only option if you want to run on Linux. Inventor, Solidworks, AutoCAD, etc, are all borked even in wine.
I never really cared for onshape/simscale or fusion. Maybe I am just oldschool but the whole browser based thing didn't sit right with me for CAD stuff.
I've worked professionally with a lot of CAD systems in the past (Caria, Solidworks, Siemens NX, Creo ...) and Onshape feels so refreshing compared to all of these "old school" CAD systems.
The git like system to manage to manage version for example works extremely well, performance wise it can be used on a potato and being browser based it can be used on Linux.
The design process is extremely smooth and intuitive.
My only problem with it is that unfortunately all the data is cloud based and it requires a constant internet connection but so far I have not found a worthy alternative.
Yeah, the versioning and operations history functions a similar to an always refreshing l pdm suite imo which can be handy but I never found it to be all that much better for my needs. I didn't play with the version merging functions much though. The only via internet aspect was a dealbreaker for me from a functional and security perspective.