I just got stick war 3 a few days ago, so this idea is mostly theoretical. I also have a large bias towards stick empires, which I enjoyed a lot.
I think it would be better for the balance of the game overall if, at the beginning of the game, players chose a faction to play as and a deck of upgrades to go with it, instead of having units included in the deck.
I think this makes sense, because then factions can be balanced as a whole, rather than developers having to balance every individual unit. If the units of a faction are provided as a set, you can balance factions by tuning units from that faction. For example, if Chaos has very strong heavy melee units, Chaos can be tuned as a whole by nerfing their ranged units or their spellcasters. This makes balancing easier, because you know what unit combinations you can make, and you can make small adjustments to the faction as a whole by tuning the units in the faction. On the other hand, with the current deck system, players can combine any set of units, which makes balancing tricky. Individual units may be balanced on their own, but when combined with something else, they can become overpowered.
Secondly, having units included in the faction you pick instead of the deck you pick ensures that players always have something to counter what the opponent is doing. In the current deck-building system, every unit has an immense opportunity cost that discourages you from selecting too many units. Many of the top decks at high levels of play have only 2 or even 1 units. This sort of system reduces lots of games to the matchup. If you opponent brings something that counters the units you brought, you don’t have many other choices. Having the player pick a faction allows them to have a varied set of units that always enables them to respond to what the opponent picks. The system of picking a faction also reduces the opportunity cost of picking units, so units like the bomber who rarely get picked will have a chance to shine.
