One thing I think would be a good addition to the existing gameplay would be adding RNG elements for more probabilistic / emergent behaviour like equipment fail

One thing I think would be a good addition to the existing gameplay would be adding RNG elements for more probabilistic / emergent behaviour like equipment failures and ageing, natural disasters, statistical variance in the performance of individual units of same types, manufacturing defects, etc. Also other things that reduce gami-ness; Gaminess kills immersion in my view.