I personally don't think that the BBC should be funded through adverts, or if it is, the adverts should be short and limited to the ends of programmes. One of the things that I like most about the BBC is that you can sit down to watch a show, knowing that you will be watching it uninterrupted.
I wouldn't mind if the BBC were state funded to a certain extent as well, because of the services that they provide that we don't have to pay for via the license fee (radio, website...)