Why would you need more than one RE for that? Key is to win two first engagements and then snowball, one RE squad is enough for that. The issue is, or the ability is effective and using it in proper condition wins you the engagement, or it is not and it is useless.
Abilities and grenade that have such impact on each engagement that they should come a bit later, around 3-4 minutes, not before. The only exception is for the anti-garrison.
Make it their vet 1 then and make it useful.
But again, if they are using it in the first few engagements they are really just tying up a squad hoping to let the others work. Suppression reduces incoming damage doesn't it? So it's slowing movement but not harming them out side that. The RE would still be vulnerable and immobile right? So if say it's a match up between sturms and volks against RE and rifles you would volley the sturms charging so your rifles could womo the volks. The cheap RE are tying up an expensive squad but if the volks turn on the RE instead of the rifles they could force them off and then it's battered volks and sturms against just rifles. Theory crafting is easy of course but that's all we have. That and comparing the old insta pin to the current never pin or even suppress...
Volley fire is in the same boat as demos- noob traps designed to waste resources as they are so ineffecient.