"Useful" conferences?

Since I received many personal comments on the posts I wrote about conferences, I am back to the theme. I do not mean to say that there is an only way to make a conference "useful". Conferences can fulfil many purposes. One of them is to make your peers aware of your qualities. Another, is to bring together experts of a certain theme. In these cases, one has to be as technical as possible and the following discussion, if there is any, may also be quite fruitful and technical at the same time.

However, I am not primarily dealing with this kind of conference now.

1. First, because I have never been part of such a small and fruitful group of experts, and hence I tend to even doubt about its existence. I have rather learnt a lot from people coming from different fields of expertise. Apart from Western philosophers/historians of Western philosophy, who often opened my eyes to problems I had overseen, I benefited from contacts with historians of art, political development scholars, sociologists, theologians and so on. This may have to do with the fact that my alleged field of expertise, "Indology" is in fact hardly more than a label for "whatever has been thought/done/said in South Asia, no matter when".
2. Second, because I think that addressing a wider audience (at least that of the whole academia) can be fruitful both for the speaker and for the audience. To address a wider audience means, no doubt, to leave aside many details. Hence, one writes essays for technical readerships. But I do not think an audience would be able to follow these details when they are presented orally. Hence, why not rather forget about them (if they are unessential) and focus on the main point? Simplifying means choosing what is essential and what is not and this critical task can only be done by someone who knows the subject. Hence, it is not at all an easy task, nor does it demand a just superficial domain of the subject.
3. Third, because conferences who are honestly 'oral' are funnier, lively and non-predictable. Hence, they are more likely to impress one for a long time and to mark a significant shift in one's intellectual life. Nor can I see any more important task for a conference (as distinct from an essay in a scholarly journal).

What are the ingredients of the type of conference I am thinking at? In general,

–Surely, no reading.

–Papers have to be pre-circulated. Even if not everyone is going to read them fully, someone will and most will at least have a glance at them.

–Not too much advertisement (too many people may ruin the atmosphere: they become a public and no more a critical audience).

–Most important, chairpersons have to prepare speakers. But how?

Apart from the above, speakers should pick up a fundamental question, one which is likely to be understood by even lay listeners. In the last conference I attended, a speaker, Rosaria Compagnone, decided to speak about the Padmasaṃhitā's role in the Pāñcarātra tradition. If the subject sounds boring, have a look at how she started her speech: (I am quoting by heart) "The Padmasaṃhitā is the key text of the Pāñcarātra religion, but it contradicts its main tenets. It is in favour of castes, rituals, etc. How is this possible?". I totally disagree with Dr. Compagnone, but she succeeded in making everyone's eyebrows rise.

What do you think?