Multiple bases do not allow you to produce troops more quickly. In the end, the allow only for increased income at the same output rate. TS is littered with logic gaps that are symptomatic of its main problem, like it or not, you will have to baby sit your troops if you want to get anything done. It's no surprise that the map is largely concealed at the beginning of the game. What is a surprise is that apparently every single unit in the game has the line of sight of a deaf, myopic bat.
Elevation makes for little difference.
Frankly, this makes scouting a tedious chore. In a particularly masochistic twist, there are rules governing what you can and cannot use to scout. Love to know who decided that you couldn't use aircraft to scout. In short, ambushes are frequent. Expect to set off your enemy's defenses more than once, because you couldn't see them until they were five feet in front of you and firing.