What is the problem with the diode?
You may know that a diode only allows current through it in one direction. In electrical -not electronic- circuits, diodes are mainly used to impede back-current. It is difficult to explain but I will try: say that you want a buzzer when either of blinkers go on. You could connect the buzzer to ground and then to the left blinker. It would buzz ehen the left blinker is on. What about the right one? Simple, go ahead and connect the buzzer ALSO to the right blinker. Then the buzzer will buzz when either of the blinkers lit.
But the undesired effect is that you have put together both blinkers, then, when either one is lit, it will lit the other one. To avoid this you can use two diodes. When the left one goes one, current will go to the diode and to the buzzer, then via the cable to the right one but it will find a diode in reverse, thus it won't make the right blinker lit.
As I say, a diode is fairly cheap, you can put any one and keep the electrics as they were. I have bikes with clutch switch and without, sometimes I push the starter with the clutch engaged and the bike pushes forward, but never had any accident. I mean, you can't live without it, but it won't hurt you and the price of a diode is cheap insurance. More than that, I appreciate the sidestand switch, a few times I have run away with the sidestand released.