While I'm not a fan of borders/passports/... I don't think the OP can influence any of that, so I'll stick to the point:

I've used IRIS before. I have Global Entry, and use that all the time. I've used the kiosks in Sydney. All of these are great! The less time I need to spend in line, the more time I can spend at the destination.

Since you're consulting an EU project, I would strongly advise you to give the ability to those with an EU (or Schengen) residency card to use some type of automated gates, or at least the same lines as the EU/EEC citizens in order to speed up the border process, similarly to how the US allows permanent residents to use citizen lines. There is a lot of discrepancy between how border agents in each EU/EEC country deal with those who have a residency card (and I'm sure it extends to other categories too) so more and better training is needed.