I prefer flashing amber with enforceable sign, "stop for pedestrians". That way, even if it's flashing amber and there are no pedestrians you can use caution and drive through w/o stopping.Why not a manually controlled "red" light for pedestrians to use? I love the idea of roundabouts, but they are definitely not pedestrian friendly.
http://www.e-laws.gov.on.ca/html/statutes/english/elaws_statutes_90h08_e.htm#BK221
Flashing amber
(17) Every driver approaching a traffic control signal showing a flashing circular amber indication and facing the indication may proceed with caution. R.S.O. 1990, c. H.8, s. 144 (17).
I don't like the idea of manually controlled "red" light; if nobody is crossing, I'm waiting for no reason; it's inefficient and contributes to congestion and traffic. That's the #1 thing that gets under my skin, when traffic is stopped in all directions and nobody is moving... this happens with faulty advance-green sensors.