See if you can get it adjusted properly. If not, the shift dog/gears could be worn. Make sure you have a solid forward. You can milk your way thru reverse, if need be. Remember reverse should only be used at low speed. if you need it at high throttle to pull your butt out of trouble, you have not planned your approach, at least IMO.
I had an old Fat Fifty. I could get neutral and one gear, due to worn linkage (J/E are the "kings" of linkage, BTW) and worn gear/dog mating surfaces. I chose forward as my gear of choice and was real careful when docking/beaching etc. It is really not that much of an issue, once you get used to it.
Gears/dog were $300 ea for a 30+ year old motor, at that time. I thought that out of line, and if you ever had a Fatty, you would agree.
Of course, in those days we had water skis that had only the front binding and the real Salom toe piece. The rest had fallen/rotted off. So only two pieces of rubber holding your feet to the ski. So, when ready to ski, yell "hit it", and when the boat takes off, jam the ski on your front foot, drag the other one, and do a deep water start. Once up gingerly put your toe in the rear binding, or you will kick the ski off. Surprisingly, once up on those two pieces of rubber bindings, skiing is pretty normal. Off the subject, sorry.