Making a shooting board was also one of my first tasks, and while mine is only made from scrap particle board using dowels and screws, I don’t think that I will make a new one just for the fun of it. I’m still pretty happy with mine.
@george Hm, your wedges don’t look very wedge-shaped to me. Do they wedge properly in the mortise or do they just sit in there moving freely to the left and right? Especially the 90 degree one looks like it doesn’t remain in the mortise by itself. If they wedge properly, then I guess some corrective measures like the ones suggested above might work just fine. if not, instead of making a new board you might also consider to remodel the mortise for the 90 degree fence and make a new wedge for it. That might be a shorter route. Just my two cents.