If you do a proper rebuild its really not worth it. This is more of a refresh. Rebuild would be boring cylinders, over size pistons/rings. Possible new rods. On a Kawasaki probably new valves and cut the seats...some engines you could grind the valves.
And yah, at a dealer none of this is really worth it anymore. New engine with a 2-3 year warranty is the way to go. Deepest we go in anymore is replacing a cylinder head when they overheat and a valve guild decides to move. Even that is not great since generally the other side will need the same treatment at some point and if you were to do both sides at once...you would probably be better off with the new engine and warranty.