Friday Afternoon Playtest

nah missle turrets are actually pretty good choices, because they do ok on both ground and air. not the best of the best, but its not a poor choice imo.

Not even a Holkinks?

Seriously, not even a mobile artillery?

that is plain silly. yesterday I played a bunch of pretty much ultimate turtlers - one giant wall fencing in 1/3rd of the planet, with a forest of triple lasers and flak's behind.
I broke through that with a few holkins and some (LOTS) tanks. don't tell me that would have been harder if it had all been missile turrets.
and yes, it would probably have been harder if they weren't focusing their efforts on other planets, but I believe we're discussing the merits of the structures themselves.

The main factors are the distance between the units and the tower (if they are too close the weapon speed will ensure a hit regardless) and the angle of movement between the units and the tower (When this is close to 90 degrees, a miss is almost guaranteed, given sufficient distance).

If you moved in a circle, you'd be nearly 90 degrees at all times, so it would constantly miss.
A square would involve changing angles; nearer the corners you are more likely to be hit, as the angle is no longer 90 degrees.