Mining in darkness doesn't sound like a good idea. Atleast make it that you have a free small light to carry around and then if you want a light that has a bigger range, you can always buy a lantern.
Also personal buffs sounds like a neat idea. The main thing I think you guys need to contreate on, is making a reason of why you shouldn't just go to Red_Guy's instead. You need to make some killer features that other mining mods don't have. Good luck on the project though, I'm all for a new mining experience.