I disagree on asteroid bases, it's always good to have more variety in the scenery. Though I don't know how common FDev have made them. It'd suck if they're rare. Same to megaships etc.So yes multi-crew lets you do stuff togethor in a new way, but in truth you're generally just doing less of the same stuff you've been doing for 2+ years basically...
Note: Asteroid bases underline your point perfectly. Do they offer absolutely anything new, for example new gameplay/depth for piracy? No they're just pretty reskinned new stations.
Otherwise you're exactly right. The gameplay content is the same - same incredibly simplistic mission scenarios, same incredibly simplistic/meaningless trading/mining systems & 'dynamic' economy, same inability to find out anything about the 'evolving' storyline of the game other than reading gigantic walls of text on the forums or whatever.