If it were me i'd order them like this:
- Discovering Your Authentic Self - (personal identity)
- Dealing With Isolation and Loneliness (shunning)
- The Five Stages of Grief/loss (Kübler-Ross model)
- Treatments & Interventions - seeking treatments from working with mental health professionals to self-help
- Examining Our Beliefs: Identifying the false and harmful (dysfunctional) core beliefs which are the root cause of our on-going difficulties after leaving
- Psychoeducation - this is closely related to #2 above, but is frankly more technical
Although all of them are important, it'd be difficult to cover all of them sufficiently in 20mins so i'd go for the top two there.
Discovering your authentic self: Reason being, so many ex-JWs i speak to tell me that they're still "finding themselves", and about 90% of them slip up and still say things like "when i was in the truth...". The loaded language is still there, and until it's removed they'll still have some sort of psychological/emotional connection to the cult. The advice I give to ex-members is to "go nuts". Take a week or even a month of doing all the things you wanted to do but were never allowed to. You'll learn which things you like and which things you dont like. And now, at least you'll have your own reasons for not doing X, Y and Z rather than "the Watchtower said". Also studying anything/everything that interests you too. You'll discover the real you and hobbies/skills you didn't know you even had.
Dealing with isolation/loss is a very important one. In fact, it's one of the reasons many people dont even bother leaving. The fear of the unknown, uncertainty if they'll ever find friends or have their own family. It also helps them to convince themselves it's "the truth" when they're facing cognitive dissonance.