I'm not saying it's perfect, but I have found having the "Toggle Light Source" option when carrying a torch at least more convenient than in EA when we had to actually swap our melee weapons around if we wanted to use a torch.
I do wish that we'd toggle back to our melee weapons when just clicking the melee weapon icon to the right of our portraits, though. It took me a while to work out that I have to re-click the "Toggle Light Source" icon again before I could melee attack with my normal weapons. Or at least I think that was what was happening.
And I agree it would be better if we could actually move a light source into the slot and out of our inventory so we didn't sell it by accident. I also wanted to be able to use the lanterns we found in the shadow-cursed lands, but I think only torches are allowed!