Why even use the Galaxy client? The game install files can be downloaded and installed without any client. More importantly, they can be backed up!
- Updating multiple installed games without me having to check for new versions
- Update using the client is also faster, most of the time it just downloads small patches, that are not always present as offline downloads for most of the games
- Check and correct files of possibly corrupted games faster than me having to install the entire game again (this is particularly useful for 30+ GB games)
- Integrated forum pages, store and account, without me having to reconnect every time to the site
- All my games accounts in a single client (GOG, Steam, Epic, Battlenet, Indiegala, Itch.io, Ubisoft, EA, Humble, Fanatical, and also manually added local games), with single aggregated entries for same games on multiple platforms, I can easily search if I already own a game in any of the connected accounts in a simple way: CTRL+F -> game name
- TAGS !!! This is the most useful function for me, I can put TAGs on all the games of every connected store in a single client !!!
- Filtered views, that with the help of the TAG system can be used for every kind of aggregation of games from all the stores in a single window
- It is required for online games
- It is required for cloud saves
- I started to like gameplay time statistics for every game I have
- I don't mind very much achievements, but is cool to see them listed in play statistics
It has a lot of missing/unfinished features, but it is the most usable launcher for me compared to the clients of the other stores, and even Playnite, that I tried a lot to use in a reliable way, but I always go back to Galaxy because aggregation of games is really useful.
I hated it at the beginning, also because I was forced to install it as it was the only way to get all the DLC for Dying Light, those weren't available offline for a lot of time, and the devs corrected the issue only after months... but also that game have online gameplay modes that are really fun to play... so that's it I needed the client...
Then I started to appreciate the various added functions that I had to do manually before using it... like updating or making sheets with lists of all my games...
EDIT:
Just a little better explanation about the "same game aggregation" and the TAG system, because it's really the bestest function ever.
Let's say I own "Batman Arkham: Asylum" on Steam, Epic and GOG.
The client, in a filtered view containing more stores will show a single entry of the game, and on that entry it is possible to select what version of the game is the default to be used.
Now let's say I install the GOG version, the "installed" view will show always that single entry.
Then I TAG that entry "Completed".
If I then go to the "Steam" view, where I see only the games I own on that store, I can filter away "Completed" games, and that game will disappear from the list even if I never played the Steam version !!
EDIT:
By the way, the GOG staff added more hours to the maintenance advice.