My current proposed Magus fix

[Capn Cupcake]

So it's pretty well known by now how atrocious the odds of landing a Striking Spell actually is, and it doesn't save any action economy to boot. I personally am fine without getting an action economy boost but the accuracy is a real hard math problem and I've seen a few different ideas. Below is the one I'm currently proposing:

Striking Spell: It now only applies to spells with attack rolls but the strike automatically applies the spell a la Eldritch Archer. This removes the weird crit reliance it has in its current iteration and actually gives the class some oomph for spending all three actions towards a single benefit. It also leads me nicely into my next fix which is

Rend Magical Defenses: Whenever you successfully Strike an enemy, they take a -2 Status penalty to the next spell you cast before the end of your next turn. This creates a very nice through line from Striking Spell, and what's even better is either side can be ignored or focused on as you please. You can focus strictly on attack spells via Striking Spell, focus squarely on AoE and debuff spells with Rend Magical Defenses, or combine the two with something that looks like Cast Striking Spell > Strike *next turn* Cast Saving Throw spell.

It's an adaptable, flexible model that allows for versatility and for the Magus to overcome it's slower proficiency, but only as long as the Magus is willing to work for it.

Edit: PS. Paizo I did apply for that designer position and would love to hear back from you ;D

[Vessa]

PREACH!

[siegfriedliner]

If I was to come up with a spell strike fix it would go like this.

On a successful melee attack spells that rely on the spell attack roll would automatically hit and spells that require a save that save would be made at a - 2 penalty on a critical hit spells that require an attack roll would crit and spells that require a save that save would take a - 4 penalty.

[Capn Cupcake]

Thinking on this more, some other changes I would make to the class:

Sliding is baseline, but it's 1/2 speed. Anyone can slide because this edition is balanced around mobility and a 3 action trick just doesn't lend itself well. Maybe make a Synthesis that gets full speed on a slide, but 1/2 speed is for sure something all of them get.

Also damaging focus spells. Things like the Fire Ray domain spell or Tempest Oracle's initial 1 action Mystery spell. This gives it some reliable flexibility from time to time without making its round to round options too strong. Once again, a package that works with itself which it currently just does not have.