I'm going to disagree with the quality of the Magus spell list being poor. More specifically. I don't see what makes it so vile or forces him to be a blaster wizard. Are there a ton of damage spells? Yes. But that's not all he has. In fact, he's got a great list to buff himself and debuff enemies as a gish fighter.
Level 1: Grease, Enlarge Person, Silent Image, Vanish, Color Spray, Shield, Obscurring Mist, Magic Weapon, ray of enfeeblement
Level 2: Alter Self, Glitterdust, Mirror Image, Web, Pyrotechnics, Minor Image
Level 3: Displacement, Fly, Haste, Slow, Greater Magic Weapon, Major Image, X Shape I, Gaseous Form
Level 4: Black Tentacles, Dimension Door, Wall of Fire, Wall of Ice, X Shape II, X Form I
Etc.
And just because Polymorph is not what it used to be (totally broken) doesn't mean it still isn't useful. It still allows your character to gain abilities like tremorsense, blindsense, tiny size, huge size, flight, and immunity to critical hits. This lets a Magus at least have the option to be able to solve problems a fighter can't.
I think you're forcing the class to overspecialize when it doesn't have to. It would be like talking about he Bard as only a melee combatant or only a spellcaster or only a party buffer. Certainly the Magus or Bard can focus in those areas, but it's not like they have to give up up their other options.