IBM OS/2 Warp cames with many things. Some are important for the OS, some are nice to have, and some are things that used to be interesting time ago, but now are irrelevant.
So I decided to make a little exercise and run OS/2 Warp 4.52 on a VM and see all the stuff I can remove from it, and just have base OS, running with GUI. So I removed TCP/IP, MPTN, network support, a lot of the software that cames to the platform and did a little inventory and which files remained in the OS.
Here it is the spreadsheet.
On that list I marked what can be easily replaced (green) and what currently have a replacement. OSFree project has produced some open source binaries that can replace some files.