The real world GPU rasterization performance jump has to be at least 2x over the base model for the Pro to be appealing to a decent percentage (20%+) of the existing PS5 userbase. 1.5x wouldn't cut it. The price hopefully won't exceed $500 (discless) and $600 (with the disc drive).
The "real" PS5 Slim may come out later near the end of 2025 at $300 (discless).