I've run games with multiple Threshold teams against lurkers. I tend to build the Lurkers with one leader type for each threshold team (so three teams would be against a lurker group with 2-3 models with leadership), and then just let all the threshold teams activate as one (players decide each turn in what order).
I have tried it with multiple teams with alternate activations between players and lurkers, not sure about that to be fair, but fun (as are any games of this).
Fully agree with the 'do not go with the silly big monsters just because you have the BP' comments, though if your building themed lurkers, that should not be a problem. As a rule, I tend not to allow any model with a BP value of equal to the highest team level + number of teams (say 3 teams, highest one with 17BP, would limit you to a 20pt Lurker model).