Necrons don't really need many tactics: shoot stuff until it is dead and try not to get assaulted. It works for me.
yeah ... but not getting assaulted is sometimes rather tricky when you consider Jumpmarines, Stormboyz Drop pods and fast transpot vehicles ... so I really like the idea of setting up my troops so that the enemy has no chance getting at my warriors and has to take out the cheaper Scarabs first
Anyway .... there are some possibilities to get out of CC alive as long as you don't have bad luck
the few times I was caught I survided luckily with passing my Ld tests and then pulling my warriors out with a Mono or a VoD .... anyway getting caught in CC was those time a fatal misstake by myself so you are right in a general way: