Theoclymenus: How on earth do you keep all these games updated, assuming you are an offline installers kinda guy ? That’s partly (but only partly) why I’ve slowed down buying games tbh. Especially if you buy games which seem to get updated every few hours (Hello, Tunguska : Visitation !)
I just run these four commands, and they all get updated (= all updated or new files/games downloaded, and obsolete old files moved to somewhere else where I can delete them when I see fit, and all files' integrity verified that they are ok):
python gogrepoc.py update --lang en --os windows
python gogrepoc.py download d:\GOG_installers\
python gogrepoc.py clean d:\GOG_installers\
python gogrepoc.py verify d:\GOG_installers\
Ez pez lemon sqez. You can even enter those lines into e.g. gog.bat text file, so you need to run only gog.bat to run all those commands.
I do that max once a month (or less) though, don't want to waste GOG resources too much. So if Tunguska has received ten updates during the last month, I am not redownloading all of them, just the latest one.
In a case like Tunguska or some online game which gets updates often, I'd probably want to play them through a client like Galaxy or Steam, just so that it is always up to date when I want to play it. With a bit older games which rarely or never get updates, offline installers are preferred. I usually use offline installers because I tend to play older games, e.g. currently playing Legacy of Kain: Defiance (2003).
EDIT: And as I mentioned, I have a 18TB WB MyBook USB hard drive, plenty of room for my GOG installers, still several terabytes available. Before that I divided my installers to two 5TB USB HDDs, but they started to become too cramped so I moved the files to the 18TB HDD and the 5TB ones got a grand new life and purpose (storing my pr0n collection, mostly).