High Points:
Capture Points: Several towns within each zone are able to be captured by enemy NPC forces. Throughout the day mobs will assault the town, attempting to destroy the forcefield protecting the entrance, and finally capturing the control point located within the base, shutting down all the shops and removing all the friendly NPCs, replacing them with enemy mobs. PCs are encouraged to defend and recapture towns from the enemy.
Staying the in the action: Tabula Rasa has no penalty for death aside from Resurrection Sickness. The emphasis is on getting back into combat and helping NPCs and PCs complete quests and assault enemy positions. Every instance (so far at least) has some form of friendly presence within it; whether it's a small village, or a strike team waiting for your assistance. This allows you to purchase supplies (most notably ammunition) and respawn within the instance when things go sour. Zones have several waypoints scattered around the map that once unlocked, allow you to travel between them.
Moderately instanced: Each zone has anywhere from 3-9 instances of itself; by default players placed into the first instance of the zones and are also dumped back into the first one when they leave instance-dungeons. When you access a waypoint you can choose to switch over to another instance of the zone, this helps quite a bit with lag sometimes, or if everybody is trying to do the same quest as you in a particular area.
Low Points
No Economy: Aside from a trade channel, there's no real way to get access to things other than what you get in the field. This can be a little frustrating when you have an abundance of equipment your particular class cannot use.