Tau Firebase Support Cadre and 40k's First True Formation

So today, GW's Digital folks released another dataslate. This one, unlike Be'Lakor yesterday, represents a formation and unlike the FW, Apocalypse and other Expansion formations, this one is meant for use in 40k. It is a detachment all to itself and has some potency that will likely see it used. I will include the details below and then pose the question of what this means for 40k and how we play our game:

Army showcase: Urash's Marauders

Hey everyone, this is KrautScientist again. After my initial post (showcasing my World Eaters), I would like to show you the other chaos army project I am currently working on: My growing force of Traitor Guard, called “Urash’s Marauders”.

Your Questions, The Lord Solar Answers (All About Allies)

O.K. so with the last post I did, a few questions/topic requests were tossed to me by some faithful readers. So I figured I would take the time to answer the first today like I said I would!

First question was from Grazer who also writes for a couple blogs, Rogue Trader and Claws and Fists so check him out (and perhaps he will join the blog roll legion for DFG after this). His question was as follows

"I'd be interested in what you think are the best options for Allies for IG, and whether you even think they are necessary at all. 

I have used Blood Angels infantry to try and strengthen my midfield and to fight for objectives, but they are quite expensive and obviously limit the amount of artillery  tanks and flyers you can select from the IG codex."