I really like the "leaked" 6th edition rule change to hitting vehicles. Moving 6" or less and they counted as WS1, moving more then 6" and they count as WS10. So genestealers, Tyrants and Trygons had an even easier time hitting slow moving vehicles, and faster ones were still hit on a 4+ usually. I mean, when you are a HtH pro, you should be more adept then a grot at hitting a moving vehicle.
As for ranged anti-tank. Unless something shifts in the main rules about the vehicle damage table we will need some of our weapons amended to be more effective.