@J the Ninja
Well it's been quite some time you uploaded this model but since I've barely begun tweaking Lux I'm asking only now :p
I've tried to redo that glass you've shown in the end of your first post. I tweaked the "world" settings of luxball, but I can't get a clear glass as yours :
as you can see on my image, the color is less vivid, more transparent and it makes very dark areas
any advice about that ?

Edit: Forgot to ask about something else, is it normal to get so much difference with the hybrid mode ? Is path surface integrator making so much a difference ?(not only in that scene but with some others too it changes a lot) Even when I activate the light bubbles it just renders this :

Still, it seems to me that a traditional render with Path Surf integrator and light strategy one won't give the same as hybrid path one