Was a while since last but...
- balance is a fickle mistress best ignored. With npc advantages/disadvantages you can easily on the fly adjust pressure.
-when in doubt throw grenades even if the npc is bad at it. Let the grenade destroy environment
-
not just invite the players to get involved with resolving adv/disadv, drag them kicking and screaming into it. Including for the npcs
-
spend your destiny points. Do it. Do it often
-
keep the splat books to a minimum if someone wants to create their own character
-
there will be narrative chaos. Don't fight it, embrace it. Spending destiny points to steer them back on track feels less railroady than just doing it.