US traffic lights that don't have 2 'thru' signals.

[doorknob60]

I didn't think that was allowed anymore. Turn signals for turning movements are supposed to have red arrows, not red balls (since you could theoretically have both red and green balls lit at the same time, although in your example, it would appear that this would not happen).

I'm not sure what the law is in Michigan, but I thought there were some states where a red right arrow is the equivalent of "NO TURN ON RED" but a right turn on a red ball is allowed? Because there's a "NO TURN ON RED" sign that lights up when opposing traffic has a green, it appears that MDOT intended to allow right turns on red, so perhaps they switched from arrows to balls to make this clearer.

Idaho is like this. Red Arrow = no turning on red. I didn't know this for quite a while (as this is not the case in Oregon, and there are rarely signs stating no turn on red in these situations here). This makes the fact that it's legal to turn left on red from a two way to a one way street almost useless, since all the situations I can think of where it would otherwise be useful, it's a red left arrow meaning you can't do it. It makes me wonder what would happen if an officer pulled me over for turning on a red arrow. I still have Oregon plates and an Oregon licence, and turning on a red arrow is legal there. I'd imagine I'd just get an informative warning, "That's not legal in Idaho, don't do it again".

More relevant, I've seen the use of red balls at T intersections (and other intersections with dedicated right turn lanes) where they purposefully didn't use red arrows, in order to allow right turns on red. At the example I can think of, it's a green arrow when it's green, but when it's red it's a ball.
Red: https://www.google.com/maps/@43.586555,-116.55169,3a,75y,149.95h,89.04t/data=!3m5!1e1!3m3!1sh6sxRnrLG4e7GzBA0tmVkA!2e0!5s20110901T000000
Green: https://www.google.com/maps/@43.586749,-116.551953,3a,28.7y,143.74h,86.89t/data=!3m5!1e1!3m3!1sUlTghJadrH88_4YxquaPpA!2e0!5s20110901T000000

[roadman]

I'm not sure what the law is in Michigan, but I thought there were some states where a red right arrow is the equivalent of "NO TURN ON RED" but a right turn on a red ball is allowed?

Massachusetts law allows for right turns on a red indication (emphasis added) after stop, regardless of whether the indication is a ball or arrow, unless a "No Turn on Red" sign is present.  This law directly contradicts both the UVC and the MUTCD, which allow for RTOR on a red ball unless there is a sign present, but allow RTOR on a red right arrow only when there is a sign present.  However, IMO the Massachusetts law makes more sense than the UVC, because it provides drivers with a consistent situation - i.e, RTOR unless there's a sign prohibiting it - regardless of whether the red indication is a ball or an arrow.