Just throwing this out there since you cant have multiple dragons in a formation without graphical glitches.

How bout you make dragons and demons unique where you can only recruit one, but there are multiple levels for you to choose from, to replace the strength you get from recruiting many.

For instance:

1. Single Dragon = Young Dragon.

2. Party Dragon = Adolescent Dragon.

3. Squad Dragon = Adult Dragon.

4. Company Dragon = Ancient Dragon.

Demons:

1. Single Demon = fledgling Demon.

2. Party Demon = Lesser Demon.

3. Squad Demon = Greater Demon.

4. Company Demon = Demon Lord.