i play last version of Dune mod, i absolute love it, even it not same to Original but everything seem right and play really good specialize when play it on 1920x1080 that wide screen make me feel like commander some how and it feel so epic when come to batte.
but truly i think it'll be better if you allow player to build unit per factory and Palace of Atreides and Ordos doesn't seem to offer different power for now specialize Atreides i feel like this faction weakest of all since Ordos also have Airstrike [most powerful power in original version ] and Sonic Tank in this game didn't powerful as original.
i don't think one factory per one tank lead the game to spam fest, it fact it even give more option for stategy for example it allow player to have different type of unit into battle field more than before and can do proxy tactic easier than ever and since the game offer only small area to build the base it isn't that easy to get 5+ heavy factory to just spam heavy tank.
In any case, right now D2K kind of allows "spamming" anyway, because you can build a Starport, which gives you a second production queue. It lets you build units twice as fast, but with +25% cost.
The Starport's behavior will probably be changed in the future (with prices fluctuating over time), but basically as long as the Starport exists, you will be able to build lots of units quickly (in short bursts at the very least, until it becomes too expensive).