I think getting autocracy is highly dependent on your tourism strength, diplomatic strength and timing. In my Portugal game on emperor difficulty, I managed to get autocracy in the 1600's (standard speed) before anyone chose their ideology. Since I amassed lots of gold, I bought 3 factories ASAP. Thank goodness I had a CS who offered me some coal.
Eventually, every other civ (12 civs) besides 4 chose autocracy. Thanks to strong tourism and world ideology - autocracy, I managed to get a freedom civ and an order civ to flip to autocracy in the same game. Along with that, I got lots of friends, got cult of personality, and got my autocrat buddies to gang up on the non-autocrat civs. I won a diplomatic victory, but I could have chosen to win a cultural victory too as I was about to get the internet which would have doubled my tourism from 200 to 400. Add cult of personality + open borders + trade route, that's 800 tourism after buffs.
So to conlude, if you are going to get autocracy, get it as early as possible and not when several other civs have chosen their ideology, mainly order considering that civs love to expand out.
As for industrial espionage, it is rather situational but a good way to use it is to send it to mediocre/good AI cities, if you can see them and hopefully the tech steal progress isn't so long.
As for clauswitz' legacy, you should only get that tenet between turn 300 and turn 360. Too early, and you waste the ability, unless the other civs are far behind in tech. Too late and the game will be just about over if you aren't winning yet.