I've been postponing writing about this for a long time, mostly because I wanted to talk at railsconf before writing a post (who am I kidding, I just procrastinate a lot), having submitted the talk for the last 3 years without getting in I'll definetly write a long post about it.
Perhaps after receiving feedback on your post, you'll find one oe two aspects that you can refine or drill deeper on and will make a great railsconf talk for next year.
> having submitted the talk for the last 3 years without getting in
That's a shame.
If it helps any, all my talks were rejected this year too. :/