I suggest limiting access to vehicle to a certain amount of points.
Starting tanks and fighters will be free.
I will describe the rest using the example of Moscow.
The second tanks (t-26 \ pz3b) should cost about 300 points (if a player scored 300, then he can use the tank once, 600 - the second, 900 - the third, etc., but points are not deducted from his statistics).
The first attack aircraft (IL-2 \ Stuca \ Pe3 \ BF110) about 750 points.
Third tanks (bt7 \ pz3e) - 600 points.
Second fighters(yak \bf109) - 400 points.
Fourth tanks - T-28 = 1000 points, pz4e = 1500 points. (since the first is approximately equal in capabilities against infantry to the second, but is semi-useless against tanks)
The second and third stormtroopers (SBM \ Pe2 \ Bf110 \ Stuka) - 900 points.
Fifth tanks - T-50 = 1200 points, Pz3J = 700 points. (The PZ 3J is inferior to the T-50 both in tank combat and in anti-infantry effectiveness)
Sixth tanks - T-28E = 2000 points, pz4f1 = 1600 points.
Seventh tanks - T-34 = 1800 points, pz3j1 = 1100 points.
The main point of this topic is the ability to track the number of tanks at the enemy and a small restriction of spam of high-level vehicles. I wrote the price + - at random.
Well, I wrote this a long time ago. And I came up with a long time ago. The idea of @VoyoMayPL is look similar, but different, and unfortunately I saw it only five minutes ago.
Also, similar system is in the game Battlefront II and I don’t like it because there are many cases when you manage to get necesarry ammount of points to get a tank, but the game progreses to the zone that dissallows tanks.
In enlisted it would mean that I would be able to spawn a king tiger when russians are already entering the reichstag (when/if we get this map). A waste of time and effort.