When resizing a radial repeat object, holding Shift does nothing.
It is expected to constraint the rotation angle to 45°, but it does not.

Holding Alt is expected to create copies, I guess, as well.

It's grayed out. The possibilities with blends inside radial repeat are HUGE

When the artwork contains asymmetrical variable width strokes, those are converted to symmetrical variable width strokes when a Repeat grid is applied with mirroring.

If you try to align something to a symmetry object, setting it as a key, Ai will align both objects to a 0,0 coordinates instead of keeping the symmetry object in place.
Same happens when you try to distribute.

All other Repeat objects are unaffected by this bug.

I used the symbol sprayer to spray image symbols. Then I expanded the objects (until I couldn't expand anymore). I selected all the object and tried to mirror them but the menu item is grayed out. All the menu items under "repeat" are grayed out, except for "options...".

When bounding box is off, splitter control is rendered, but does not work, and instances control is missing completely.
Having the bounding box turned off does not mean a user does not want to have repeat controls. So they should be A) completely hidden, or B) shown and be completely working.

The repeat grid is awesome EXCEPT for the fact that it puts all of the objects on the same layer when expanded. This doesn't work.

I'm trying to make stickers with a dieline. It laid and and spaced them wonderfully except now I have to go back and manually fix the dielines that are now on the same layer as the art. Lame. No thanks, going back to the old way by hand and replicating a correct object.

I make a regular rectangle and try to convert it to artboard and get the attached error. If I put that rectangle on another layer, doesn't contain a repeat grid object it works.