I agree that lurkers could do with a rework. As a Queen, one of the most reliable strategies I have is to go heavy on lurkers and have them fuck the marine's rear as the entire rest of the hive stalls the marines' advance. It's worked for me eight or nine times out of ten without much modification. Over the past several months the strategy has come to work well on high pop too.
I have no problem with the concept of a powerful ambushing class, but I feel something should be done so their effectiveness doesn't scale to high numbers so well.