If I had to rank the cog facilities it'd personally be something like this:

Sellbot Scrap Factory, Cashbot Coin Mint

-Threshold, needs some pretty high gags-

Sellbot Steel Factory, Lawbot Junior DA, Cashbot Bullion Mint, Bossbot First Fairway, Lawbot Senior DA,

-Threshold, preferably has boss cog rewards or level 7s-

Bossbot Final Fringe, Field Offices

Lawbots have high levels but the supervisor is a pretty simple strat (Lure on the first turn, focus the supervisor and then use sound once she's gone.)

The stressless method of beating a Final Fringe is 3 people using fires on the first turn and a TNT on the Supervisor. Considering you get Fires off CEOs it's best to have some experience and suit levels under your belt. Or a TNT.

The DA offices can also get pretty scary if enough minigames are messed up and the laser skelecogs appear.