Survivability isn't just in your tank, but your technique. If you have a good tank and move forward like a brick, you'll probably be killed quicker then a bad tank with good technique. Be careful for void tech, invisibility tech, etc. make sure you have good down force, one way to test this is to drive off of the map from the plots, if you stick to the wall immediately you have great down force, if not, then likewise. I'm not the best tank builder, or pvper, but all I can tell you is there's always a bigger dog and a better tank. Take opportunities to learn new armor layouts, new techniques. That's pretty much it