I have finally gotten my Arbites codex to a state where I am ready to share it with the masses. I have been working on this thing off and on for over two years. This is the culmination of all my thoughts and hopes and desires for the Adeptus Arbites, and it has been shaped greatly by many fantastic ideas from various members of the online 40K community, especially those over at the Adeptus Arbites Garrison on Yahoo Groups.
One thing I want to make clear - this has been in progress for a very long time, and nothing in the list was tossed in lightly. I have spreadsheets with data on weapon effectiveness, and I have done some playtesting with certain units to make sure they work well. Please keep that in mind when you are making comments. That said, constructive criticism is not only allowed, but greatly encouraged, as I want this thing to be the best that it can be. (I plan to update it to fit with 6th Edition once it is released - hopefully that will be less work than putting this together in the first place!!!)
My vision for the Arbites army is for one that has to either get into medium to close range with the enemy, or else allow the enemy to come into such range, and then unload a ridiculous amount of short-ranged firepower, potentially pinning or otherwise slowing/hampering many of the enemy units before choosing a few key targets to charge into assault with - and hopefully either crush them utterly or send them packing. They are not as shooty as armies such as the Imperial Guard or the Tau, nor as nasty in close combat as Tyranids or Orks. They are more of a well-rounded force, though a bit short-ranged in shooting and reliant on careful planning for close combat. (Their rules make them most effective against enemies that have already been softened up and pinned down.) They even have one unit - the Suppression Team, which actually excels at receiving a charge as they have Counter-Attack, defensive grenades, an invulnerable save and the ability to cause enemy units to strike at Initiative 1. Of course, that requires you to actually coax your enemies into charging them in the first place...
So please have a look, have a think, then come back and tell me what you like, what you don't and what could be better.
Unfortunately, the file is rather large and I can't upload it directly, but I have set up two different hosting options. You can get it at either Scribd.com or box.com.
(Codex Version 1.2 - updated 4/16/2012)