pretty sure that first idea is almost exactly like what the dread tank already is except with a outline and with out the trail of smoke it produces...
the other ideas. i think fatal metor could be a skill that could be triggered by the player rather then randomly. there are buttons unused by the plugin that could lead to new ability's like ctrl + mouse 1 or 2 even the E button.
Trail blazer sounds something from anther plugin but yeah, it could fit very well for the fire tank.
I just hope who ever picks up this plugin will make it better
. (hopes for AtomicStryker or panxiaohai to take a look at it).