A mod that builds upon and tweaks the vanilla experience with a little bit of everything:
crafting, furnaces, resources, turrets, vehicles, enemies and weapons.
[Built for base 2.0 Factorio - Works with Space Age]
in a nutshell.
HeroTurrets_Redux
has solved the Turret veterancy persistence with making additional objects, which are the leveled up turrets, to keep gained levels.
Maybee this is something for you too. Works like quality does, I guess.
