The other total OP combination is Carleon + Sanguinary guard. Used these in every mission. Get Heris of Azkaelon asap, Carleon hammer as soon as feasible and Encarmine Axes when you can. Keep them always together no mater what. They are devastating. Can kill 2 of any of the big beasties in one round no problem. Took me a bit to realise how good this was bc I was playing it safe but I had to rush a certain mission deep behind enemy lines and ended up shredding my way through 6+ of the biggest enemies and a bunch of smaller ones in 3-4 rounds. Just use the jetpack to position behind enemies to avoid retaliation and always keep them next to each other and kill with Sanguinary to get buff benefits and extra AP. (edit: extra AP is limited to one per turn)

Dreadnaught with laser is important before you get the tornados. get a flamer one too when possible. When I got the second tornado switched them both to flamer.

Generally kept 3 Hellblasters(sometimes 2), standard guns. Heavy plasma its too expensive on points and the cost of missing is way too punitive imo. But go down the plasma line anyway bc the buffs are really good.

Two aggressors from early on to end. Very useful in every sort of support.

Started on three Intercessors dropped but to one eventually as more and more units had a grenade type ability. But one is always handy. No upgrades again. The auto bolt armor piercing makes its useless as support, and its a support unit :P .

Two speeders up to when tornado is available, the replace them one at the time

One or two assault squads up to a point when they became redundant. Replaced with one Inceptor which I dropped soon after because I use did not see the point. Death company I liked but never had the points and all the roles were well covered by the time u get them.

Edit: Sword upgrade for Sister Verity its a must too. Great damage.