Slayer Shock does an incredible amount of things correctly. The moment to moment pacing is top notch. The interweaving of the planning 'Strategic' loop with the action/stealth 'Tactical' loop is both simple enough to comprehend at a glance and middling complex in the way the two interact, making decisions feel weighty. Each has good Push Your Luck mechanics - enemies you can avoid confronting at the loss of the extra currency they'd drop, harder than average missions that will temporarily bring the average mission difficulty down if completed, etc.  Losing on an operation has costs, but doesn't end the run right there, so the game feels oppressive but never outright cruel.

The only real problem I've had is with the difficulty curve, which starts fairly high but then drops off a cliff. Skills remain unlocked and weapons remain available once acquired, so things get progressively easier, and additional 'seasons' either don't get harder or get harder at such a slow rate that it's not noticable. This caps the game at maybe ten hours of enjoyable play (for me), after which it becomes too easy to relish. But those are a highly enjoyable tenish hours. 

Recommended!