It's hard to say they have trouble getting a coach. I think with their current financial situation it will be easy to get a good coach. But it looks like they have their own policies and they don't want to rush like Potter's election.
At the moment Lampard's problem is to understand the new players. They need adaptation and at the moment they are not a good team. So I wouldn't expect much on Lampard to bring Chelsea better. No worse than potter, maybe that's my best expectation. In the UCL I think they also don't have as much hope as they will be against Real Madrid.
Lampard is optimistic to get Chelsea into shape, but he needs support and good cooperation from players and everyone. Some players haven't adapted well to the team, Lampard has a duty to make it better. I noticed that Chelsea need a good touch from Lampard even though I doubt it, but Yes, he should be supported instead of hated.
It's difficult for Lampard to be expected to be able to beat Real Madrid in the Champions League, but there's nothing wrong with seeing how he proves the quality of his team this time. Chelsea are a good quality team but they are just unlucky with goals.