While I am trying to get my list together and figure out what allies to run I came across some awesomeness that I wasn't aware off.

One of the problems with guardsmen is they don't have access to prescience, Although bring it down and 're rolling cover saver makes up for the lack of divination. However I realized Dark Angels are battle brothers that can easily bring Divination to the guard army. Also with the addition of the Inquisition you can have a guard army with at least 3 divination tossing psykers in it.

The gravy part is you can take the Leman Russ that can drop 5 plasma templates and give it twin linked and possibly deny cover. In translation it's perfect for dealing with broadsides and riptides, since in a turn or two it can kill either one of those units. On the plus side it has armour 14 which makes it rather hard for Tau to deal with.

My ideal is to field one psyker per plasma tank. If need be the psyker can be hiding behind the tank, or hide inside of a chimeria/ rhino.

I have to look if you can take two inquisition hqs as a choice which would be nice. I am debating on sisters or dark angels as guard allies right now. If I go dark angels I'm just taking the psyker and a marine scout squad. If I take the sisters I will take an Exorcist, a few troops with transports and Jacobs maybe, or Cannoness.

The plasma tank was feared in 5th and with the lack of mechanical on the field it can be feared again. Surprisingly the only heavy mech armies out there sport armour 10-12. What is great is that the tank still can pen armour 12.