Yes, they're very limited.
Limited to infinity.
I think you need to know how to play certain shots that are general and then practice variations of those. For example, ball hanging in pocket, need to get to about 4 areas of the table that are really different shots, the rest are small variations of those.
3 rail position shot to get to other side of the table, important in 9 and 10 ball. Since the 9 and 10 tend to be in the same place between the spot and the rail, knowing how to play shape to get to that area is important. I don't know how many run outs I have ruined and seen ruined because someone did not play for a good shot on the 9 or 8 and ended up with a tough shot on the 8, then tough shot on the 9 and missed, or easy 8 but ended up going too far down table for the 9 and ended up in the 50/50 line.