IANAPGM, but one can observe that TA and SC are indeed different RTS games in the sense that TA has a territory control focus (so perhaps a bit more strategic), while SC relies more on the micro/macro focus (workers, some skillshot abilities - which incidentally led to the birth of the MOBA genre).
Depending on how that's implemented, I could see that rapidly becoming de facto "pay to win".
I HATED the fact that Starcraft II wouldn't let me do this when it first came out.
I loved Starcraft I, but the emphasis on twitchy play meant that I simply couldn't be bothered to finish Starcraft II.
I know several of the later games, and even the first games (as far as I remember) allowed two fully independent screens with the UI buttons only appearing on the first one - I used the heck out of it.