If there's a plan for Imperial Guards, I would want to give some ideas for devs.
In the first, I would say about Faction Mechanism only, which is comparing to SpaceMarine's Orbital Rellay, Ork's Waaagh and Scraps, Eldar's Webway.
So, I will not say about units and tire.
the unique mechanism of Imperial Guards is Morale. Morale is a value which is representing how much your army have been boosted.
when your/ally units kill/destroy the enemy units/structures or capture the resource points, your army earn some Morale.
but when your/ally units/structures have been died/destroyed or your resource points have been stolen by enemy, your army will lose some Morale.
if the unit is valuable, you will get/lose more Morale.
Morale starts from 0 value at the beginning of the match, and could be negative value.
There are three Grades each side. when your Morale is growing to be positive, your army will get buffs.
First Grade of positive Morale value gives additional armor point to your entire army.(maybe +1? or +2?)
Second Grade of Positive Morale value makes your army to get increased fire rates.(maybe 10%?)
Third Grade of Positive Moral value gives faster movement speed to your army.(maybe 20%?)
and Negative Grades exactly reversal of positive grades.
Morale displays upon the command pannel, like drop pod bays. it would appear like this.
▽ ▽ ▽ ▽ ▽ ▽
maybe you are worrying about snowballs when you are losing. but it isn't necessary.
there's a unit, Commisar, can be produced at HQ, can increase Morale by executing guardmans, and it also give temporal field to Commisar, which is decreasing Morale Loss by unit death inside of the field.
Execute is basically generates Morale. it is not much, but it would help to protect Morale value from losses or restore it, and even boost up your fighting efficiency.
Execution has cooltime, so you should have multiple Commisar units.
Morale is slowly going to 0 value by the time, but meanwhile, you can interfere this process, and manupulate it by fighting or using Commisar's ability.