Hi
Larger maps force players to build big (as you want to do). But that requires a lot of performance which is over the minimum specifications of the game. Many players would get a lot of performance issues then.
I am not sure that the availability of additional land tiles can be programmed dependend on the player’s hardware. There are too many factors for that and I have never seen any game doing that.
If you have good hardware, it is always possible to increase the map size manually. It is not supported but it works pretty good.