What if we had a way to lower the action cost without resulting in massive single hit spikes to balance it the action economy with expected damage while increasing consistency and longevity of the Magus?
Rough idea here.
Spell store: free action meta magic. Store a spell or cantrip within your weapon or body. Lower the action cost by 1 to a minimum of 1. If this spell isn't used by the end of your next turn it disipates harmlessly.
Spell strike: you make a strike and discharge a portion of the magics power. If the strike hits, the spell hits, if the strike crits, the spell crits. (So one roll). When you successfully strike your cantrip or spells damage and duration effects are cut in half to a minimum of one round. You can do this twice before the magics power is fully depleted, or until the end of your next turn after casting spell store. If you have a melee critical effect and a spell critical effect. You have to choose Wich one is used when you critically hit.
Then add a feat. Where you can unleash the full power of said cantrip or spell but you add one action to whatever strike used with spell strike. So as example power attack would become 3 actions.
I know my wording sucks and probably leaves holes. But.
1- this would increase Magus consistency power round
2- it would reduce their swingy nature (with an optional feat to gain that back)
3-it doesn't require adding the fortune trait to deal with spell strike while keeping that playstyle largely open for those that want to invest into it.
4-reduces the feel bad feelings of missing with your spell strike.
5-let's you rely on your martial prowess with spell strike while requiring your casting stat anytime you would use a spell outside of it.
6-gives non damage spells a reduction in power (duration) while giving you more chances to apply.
7- balances the save spells with Magus by disallowing the 4 tiers of success in exchange for using your melee strikes simple miss/hit/crit.
I'm sure it needs cleaning up. But the general idea is there and I think it could potentially please both parties.
Why make a weird, convoluted mechanic, when the easy option is 1-action spells with lower effect outputs in exchange for the quickened spellcasting?
Because what you describe isn't a Magus. You are not combining the spell with the strike. And what you propose would result in every single spell caster multicassing Magus for 1 action half damage cantrips.