Pajama: For these reasons alone I'd certainly give it a go. It is the single click download that I really miss though, the old GOG downloader was just so easy to use and lightweight too, I would love to see an alternative.
My GUI for gogrepo.py makes it one click downloading, and further one-clicking to queue up other games.
And while my GUI for gogcli.exe isn't currently one click, it is one click to add a game (all files) to the download list and another click to select all and then one final third click to download all. I could make it all one click, like I did with gogrepo.py, or reduce it to two clicks, but what's a couple of extra clicks. I may yet enable that in an update though, as I have partially done the code for it.
And it's not 3 clicks per game either, it is one click per game plus two clicks. So 5 games would be 7 clicks total, 10 games 12. That's all files for those games, including extras and patches and DLC ... and alternate OS files.
EDIT - Actually it is 3 extra clicks total with multiple games, not 2. One click per game to add to a combined download list and one click to open the download window ... then you have the extra two clicks. So 5 games would be 8 clicks and 10 games 13.
Even the old GOG Downloader, bless its soul, didn't do so few clicks if you had extras or patches or DLC to download.
And that includes automated MD5 and ZIP file checking with my GOGcli GUI, which run's the gogcli.exe program by Magnitus.