I think that my main concern would be the frequency and quality of lookout..

It is very evident to instructors (in my UK experience of talking to some, as well as having been one) that too many pilots do not have very good lookout. There is hard evidence – the numbers of collisions – as well as instructors’ impressions during check flights. (By the way, as I have written in an article for the UK Sailplane and Gliding magazine, my lookout is not good enough either – nobody’s is, IMHO – humans are just not near perfect enough. But to get anywhere with it, one has to at least try.)

There is further evidence in videos posted by people of their flights, using in-cockpit cameras – in some, the pilot’s head hardly ever moves from the straight ahead. In others, the head is sometimes seen to turn to the inside of a turn but not to its outside.

A major feature of initial instruction in gliders in the UK is the emphasis on lookout, particularly before turning – and lookout all round, not just in the direction of turn. Is this the same in other countries?

This is repeated in subsequent flights – many instructors block the stick being moved if the student tries to turn before looking out.
I have never seen a simulator that even simulated nearby gliders that are potential collision risks, let alone seen anyone trying proper all-round “lookout” in a simulator. I think primacy is the thing here – if students do not practice this from the start, they are unlikely to remember later.

I no longer instruct, but do have check flights every year. I expect my lookout to be monitored, and commented upon if not seen as adequate. No simulator at present does that, AFAIK.

Chris N