I can assure you Gil wouldn't really make people jump at the roulette. I'm currently at around 1500 runs and after talking with multiple people who either have the mount or are going through it generally just go as DPS since there's less of a chance for you to be put into an Extreme trial. or as a Castrum/Prae run where you barely get anything for the amount of time spent.

If they take out the Extremes and make them their own roulette I'd bet it would increase the influx of people running Mentor, since more people would probably queue on the AIN role knowing there wouldn't be anything too crazy in store.

Me myself I generally do the AIN just for fun, sometimes you get an extreme that can work out, other times you get a guildhest that lasts less then a minute. All a luck of the draw imo.