One thing that can also be done is that all 1v1 games would affect both ratings RM-General rating as well as RM 1v1 ratings, where as team games would affect the RM general ratings.
for example if a newbie's first game is a TG and he won
4v4
RM - general = 1604
RM 1v1 = 1600
another newbie's first game is 1v1 he win.
RM general = 1616
RM 1v1 = 1616
If we do this, we would maintain the tradition of comparing players with only one ranking ladder that would be RM-general ratings, which would be better in my opinion. If we separate ladder then there would be confusion regarding who is a better player because one of his rating will be low and other will be high.
for example if a newbie's first game is a TG and he won
4v4
RM - general = 1604
RM 1v1 = 1600
another newbie's first game is 1v1 he win.
RM general = 1616
RM 1v1 = 1616
If we do this, we would maintain the tradition of comparing players with only one ranking ladder that would be RM-general ratings, which would be better in my opinion. If we separate ladder then there would be confusion regarding who is a better player because one of his rating will be low and other will be high.