HiroshiMishima: Which is ultimately what I ended up doing, cause I was unhappy with my previous file, having made extra gear and then realizing I couldn't sell or otherwise get rid of the extraneous weapons and armour.
Starting again is probably a good move in this case, since the total amount of dark crystals it's possible to find in the entire game is only just enough to make everything in the forge and upgrade the minion homes to the max. IMO upgrading minion homes should take priority (since they do most of the fighting), and you'll definitely want that helmet that doubles the number of life force orbs you pick up.
You can of course build and upgrade everything eventually, but only if you find every single dark crystal - and from memory the last ones are in the final area (just before the final boss of the game).