the radar item only seems a seems plot based, and only provides a visual and audio effect
I'm not sure if there is more content as after eliminating all of the enemies within the subspace area but after entering the second portal there isn't anything i couldn't see as a valid pathway and it doesn't exclaim itself as an end.
i don't know why lowering the browser window size, increases performance, but it works(my guess relates to pixels).the weapon upgrades are nice with the slow single shot, fast but weak barrage, and shotgun.
the unlock for the barrage weapon's placement is nicely done as it makes the player ask the simple question of "how do i get there" and sure enough a platform with a long delay between point a to point b is present.
the enemies require a moving in battle as their fire rate, is for a fitting term, alien.