It is likely that visual perceptual issues would have some impact on other tasks, most probably Coding. The particular kind of error that you observe in live settings (reversals) is less likely to be an issue for block design, visual puzzles, and figure weights, as none of them rely on symbols. I sometimes see reversals carry over into matrix reasoning a bit. If you were to assess for this kind of deficit, you would probably want additional testing by an OT. I would probably start from an alternate PS measure to separate speed from something specific to symbols, though since you already report reversals, and fluency appears to be a global weakness, an OT eval might be worthwhile regardless of PS findings.
