Could turn Coruscant into another moon of Endor, or a neighbouring planet.
I know why you would want that (for RotJ) but it would destroy my suspension of disbelief to think that right next door to the galactic capital is an untouched forest world inhabited by primitive natives.
I think it would make it all the more interesting, “the sanctuary moon of Coruscant” a forbidden sacred forest that no one dares to enter. Really plays up the ruthlessness of the Ewoks.
JEDIT: It could also play into the ying/yang symmetry of star wars. Dark/LIGHT, Nature/Technology which would really drive home the theme of nature winning the day in ROTJ.