TBH i gave up on Agents of SHIELD in the first 6 episodes and jumped back in when the Inhumans showed up and stayed for Ghost Rider which was awesome (they actually are better than the netflix shows at handling a supernatural character(s)).
So to me it is worth it because i honestly did not give a **** about Coulson before he got his hand chopped off and became more flawed (granted he could have always been flawed i just didn't care to watch and see).
I think the inhumans gave the show a strong sci-fi element that was to unique to it rather than before where it was oneoffs and tie-ins to the movies. I do think they did screw up by making it their sole focus and they played up the mutant-lite angle without capturing what made the inhuman different to me.
Surrogates are fine but you still gotta capture what makes the character distinct. Having Green Arrow stand in for Batman is fine but you gotta capture what makes the GreenArrow/Superman dynamic interesting and different the Batman/Superman one (for example).