At this stage of the game I believe there are several criteria.
First, as noted in the (slightly insultingly named) 'Nub Server' thread, this server might contain a high percentage of newer players. A good leader here is forced to adjust to these considerations. The Marines have adjusted as well as anyone could, entering the game with a select group of players, keeping Lambda as their primary focus, and keeping recruitment very low. Obviously placed in the very good leadership slot.
For all the other leaders, it's going to be a lot harder to see.
But there are some ways to discern how well they are doing.
First of all, with a new game, and a lot of new players, these leaders will have to train, uphold morale and keep people active by encouragement. This can easily be seen on the point charts by looking down the alliance's list.
-Are a lot of players really low in points, seemingly inactive?
-Is the fat being trimmed?
-Is there a core group of higher point players?
Second, I believe it is vital for these leaders to be active themselves. No recruit (or experienced warrior), no matter how good they are or may eventually be, wants a leader that seems to be wishy-washy or doesn't care.
Granted, people have real lives, but at this point of the game one sign of a good leader is someone who is near the top of the points chart (alliance, ocean and world), and also has a tidy number of BPs.
This shows commitment; to their players, the alliance, Lambda, and especially to their own leadership.
As I glance down the lists, there seem to be some excellant leaders out there.
But, as everyone here has indicated... only time will tell.