It can actually help a lot, but the main purpose I wanted this mod was to use a torch in the left hand together with the Illumination mod, but it seems like the mods aren't compatible. If this feature could be implemented, it would be an ideal tool for mining. It would also be nice if the item that is hold in the left hand could be seem in the left side of the screen while you are in First Person perspective. However, I think the mod is awesome, and with what I just said, it would be even more amazing.
Thank you for the review! It is still in development, so not quite feature-complete yet.
I didn't even know about the illumination mod, I will definitely check it out and see what I can do. In the mean time, you could swap it out for the wielded_light mod which does the same thing and is in fact supported.
Regarding the first person mode, the only way I can think of doing that would be a HUD overlay. However, that would also show in third person mode and would look rather strange. I was planning on adding that as an optional setting but keep it off by default.
Edit: I had a look at illumination and it doesn't look like that mod offers any way at all to inject additional behaviour without redoing the entire mod. My recommendation is to stick with wielded_light (+ 3d_armor_light if you want armor support) instead. It does everything that illumation does but is easily expandable and also supports dropped items as light sources.