Wow... I haven't played in ages and oh boy this game made progress 
I noticed a few issue with reinforcing your armies. But also armies in general.
T2 armies are extremely tedious to manage because the leader just keeps on dying which means the army keeps disbanding...
I don't know if this is intentional to keep the players busy in the heat of combat or not but if it isn't well... it's very annoying and I had an extremely hard time keep my folks together.
now with this issue comes another one. And that one really gets at ya like bruce lees one inch punch 
say you want to create a full Meta unit of 128 logistic and lets say you do that through the reinforcement tab. So you queue up maybe 128 Artemis and because you thought yeah One full army may or may not be enough we just do it again for a 2nd army.
Now this bug doesnt have anything to do with managing two armies but simply because right at that moment there are 256 Artemis queued for Production.
Now what happens when the leaders die?
- The army gets disbanded? yes!
- the production stops? No!
- are you able to see the buildqueue? NO!!
- can you cancel the production????? NOOOOOOO!!!!! -.-"
- does destroying your factories help? ............................................................................................
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no building new factories will have them pick up on the work 
Needless to say I stopped building large armies in order to avoid getting devoured by the chaos :/
Then there's this issue where you can't evenly spread your production between two armies calling for reinforcements unless you micro like a boss and keep switching back and forth.
I would love some sort of feature where normal production cycles through armies when calling for reinforcements With the added feature of a priority queue, so you can manually push through a couple of units towards an army that is taking heavy losses.
Press E normal queue armies will receive unist roudn robin style. press ctrl+E units will be entered ito priority queue.
Obviously priority queue gets handled before normal queue.
The summ of those bugs/ lack of features make it extremely tedious to control a large force
I gotta say microing Supcom wih 300~ 400 units and 20 factories has been easier for me to micro than just managing two Meta units and 5 factories....