I played my best in the mid '70's, like you. S/V, mostly eastern forehand grip, and 2hbh for me.
Around 2007, I decided my eastern forehand wasn't cutting it against the juniiors I often end up playing with, the ball bouncing high to both sides. I slice my backhands, taking them late out to the side, skidding them low over the net to deep NML, bouncing maybe knee high at the highest.
But the forehand was the problem, so I switched to a strong SW grip, almost full W. Now, I hardly ever hit too deep, unless it's a mishit or mistake. Most of my errors are short balls, but still go over the net.
Practice is the only cure. Aim 3' above the net instead of 18", and add more spin, less ball speed, until a winner is needed. LOOSE grip for rally balls, tight grip for winner attempts.