Actually allow Corona Scatter to scatter objects with a certain array / regularity over a surface would be nice.
That is already possible in Chaos scatter in aforementioned position distribution mode. It has limited functionality, but certainly could be useful in some scenarios. Give it a try.
Or make it snap on polygon centers, edges or points could also be nice.
Agree with that. This feature could be useful and i think it shouldn't be too hard to implement. Even super limited 3ds Max's native scatter can do that, so Chaos scatter should too.
For relatively non-complex distributions, 3ds Max's array modifier (tool as well) can be very handy as well.
It just may have some limitations - e.g. CoronaLight cannot be arrayed with the modifier.
The OP originally posted this topic in C4D section, i think it's unlikely that 3ds Max array modifier would be much useful to him :]