When I use lots of lightblocks/barriers in my maps, the game is lagging because of the faces that are being rendered for the visible blocks. I suggest adding face culling for them for performance (for example, face culling like leaves/glass blocks)

originally the idea was that it would be beneficial to be able to tell how deep it is but yeah I think it would be nicer to just cull, especially for some rooms that are totally full of light blocks.