Spellstrike and increased Critical Modifier

[Grimslade5]

How unbalanced would it be to allow a Magus's Spellstrike ability to multiply the spell damage based on the weapon's critical modifier?

Right now there really seems like no reason to use anything other than a scimitar/rapier because of the criteria range. If it was allowed to use the weapons critical modifier the Magus would have additional attractive options.

Assuming keen or improved critical, the Magus could choose between:
Scimitar/Rapier 15-20 X2
Falcata 17-20 x3 (requires EWP)
Pick 19-20 x4

So with the pick there is a 10% chance of threatening a 20d6 (40d6 if using intensified spell) shocking grasp. Compared to a 30% chance of threatening a 10d6 (20d6 with intensified spell) with a scimitar/rapier.

[Mackdose]

The original version doesn't have that limitation. It was errata'd to be capped at x2.

There's a combo using the traits Wayang Spellhunter and Magical Lineage that would allow the Magus to intensify -> maximize at either +1 spell level or +0 spell level depending on GM ruling.

I assume the developers thought that a weapon crit modifier of x3 or x4 coupled with the trait combo was too strong, so they capped the spellstrike modifier.

[Psyren]

It is strong - how many 10d6, 15d6 or 20d6 weapons have you seen? Rolling those twice is bad enough, never mind things like Arcane Accuracy to make confirming those crits a breeze.