I used the twitch app for minecraft modpacks and i knew that you can install mods for ksp throught there but i never tried it..
I'm actually taking a look at it right now,it looks good so I maybe try it!
As for CKAN
I like CKAN (especially because i'm extremly lazy,and im not installing the whole RO collection for myself(Plus is something goes wrong i can blame CKAN not myslef :P))
Now for curse:
Direct NOPE for me,I don't know why(Oh I know!.The hundreds of adds! there(Im exagerating a bit BTW)) and as i said before if I wan't to download a mod i go to CKAN if it isn't there i go to he forums were i rarely see a link to curse.(well i saw quite a bit but its often shadowed by github or spacedock witch i prefer quite a bit more)