I posted this to my LS forums ... I left out Apkallu Breeding which would be a good one, but these are the ones I like ...
Here are some Assaults that are easy to farm and take very little time. I have arranged them by rank, and highlighted the ones I actually like to farm in bold. Note: Leader gives 10% additional points, completing a mission for the first time gives a 50% bonus, and there is a 10% reduction in points for every member that you bring above 3 members.
As you can see, at any rank there is at least 1 Assault that people can do regardless of jobs and get 4400+ points from 4 tags in less than an hour (in most cases, around 30 minutes).
Private First Class
Assault: Lamia No. 13
Zone: Ilrusi Atoll
Points: 1200
Minimum Participants: 3 (at least 2 need to have dispel in main job or sub job ... BRD sub was reliable for me)
Time Required: around 20 minutes
Task: Lamia No.13 wanders around with 3 fomor-type minions. If you cast Dispel on them, it will dispel their "charm" and they'll turn in to NPC-types and attack the Lamia. She will occasionally use the charm ability as a TP move, and it is AoE on whichever group (you, or the fomors) has hate, so you must re-dispel them as this happens and make sure that your other pt members are out of range if it is going to be a pt member getting charmed. You basically just keep the NPCs alive until they kill the Lamia. Doing anything to the Lamia directly will get you hate and it will be very difficult to shed it without getting charmed, but curing the NPCs will not get you hate.
Lance Corporal
Assault: Breaking Morale
Zone: Mamool Ja Training Grounds
Points: 1333 (for all the chests)
Minimum Participants: 3 (any jobs)
Time Required: about 10 minutes
Task: There are 8 chests on the map. You must open the chests and return the items to the NPC without getting caught. Trainers catch you and send you back to start, while Recruits just aggro (you can shed aggro by getting caught by a trainer). You can get a costume which does 22 damage/tic while it is on by using the Viscous Liquid on the map. Being in costume will prevent aggro. Reward is variable based on how much treasure you get. Chest locations are on the Wiki link.
Corporal
Assault: Counting Sheep
Zone: Leujaoam Sanctum
Points: 1166 (for 5 sheep)
Minimum Participants: 3
Time Required: about 10 minutes
Task: I don't remember much about this one, but I'm told it is quick and easy for Leujaoam points. Best bet is just to read the Wiki link.
Assault: Siegemaster Assasination
Zone: Lebros Cavern
Points: 1100
Minimum Participants: 3 (tank, DD, and healer work best)
Time Required: about 10 minutes
Task: There are 8 trolls. One of them is the guy in disguise, but you won't know which it is until you kill it and it tells you that you won the Assault. The trolls will repop, but the guy you want will never be a repopped troll, so keep track and only kill the oriignal ones.
Assault: The Double Agent
Zone: Mamool Ja Training Grounds
Points: 1200 if you capture the right Qiqirn the first time
Minimum Participants: 3 (being able to solo easy Puks is a bonus, but just being able to stay alive until someone else can help works too)
Time Required: 5-10 minutes
Task: You must question the Qiqirn. Some of the answers will be worthless, but others will tell you what direction the spy is in. Sometimes it is something like "close", "really close", or "really really close", while others will give you a direction, and others will give you an exact distance (in the same units the windower distance thingy uses). The spy will also lie, so if you have 1 Qiqirn that gives a direction that is completely different from everyone else, it might be a spy. Capture the right Qiqirn, and you win. More info at the Wiki link.
Assault: Building Bridges
Zone: Periqia
Points: 1200
Minimum Participants: 3 (any jobs, completely naked is fine)
Time Required: 5-10 minutes
Task: You must touch a Bridge Switch in the North, South, East, and West corners of the map. Also note that the Rune of Release is in the very center of the map. There are NPC Lamia wandering around. If one sees you, it sends you back to start. You just have to dodge the NPC Lamias on the way to the switches and the Rune.