If you can build rail centers, players get a risk/reward thing going on that develops player options. They buy something and it benefits them, the enemy can negate them and it costs them using as bomber which in turn costs the enemy the use for another purpose he did not intend.
If i did this “stop land units moving two spaces” you disrupt all currently known strategy…basically invalidate it with one sentence, then you make combat moves problematic because tanks are usually behind the front lines because they move two and they are protected behind the front lines ( in the case of the German-Russo conflict). With your idea the whole panzer army needs to be on the front line and have lost the options to move north or south two spaces, and just have to fight whats next to them. You with that rule ruined the game. thanks.
It appears you never played global 1940?
Just please stick to the actual rules and find a pretty idea that adds to what players can do in the game that was not already accounted for.
How about an idea regarding neutrals? or Tech changes to alter SBR raids ( perhaps jet fighters taken in as escorts fire at 2?) ? ?
Something from that mind, that generally smart mind you have…