So what level 9 spell do you think Swordmage's need?
And what's the point of having magic missile, fireball, lightning bolt, and cone of cold if they are all melee?
Because if your doing a new class, and have to modify every spell, why not make something new instead?
Like...
When you make a melee attack, you gain a mana point up to your level. These points last until the end of combat.
You can then spend mana points on the following effects.
Add Elemental Damage for 1 point.
Teleport for 1 point per 10'.
Elemental Burst: 2 points, all creature within 10' make a reflex save...
Greater Elemental Burst: 3 points, all creature within 10' make a reflex save...
Ect...
At level 17, the Swordmage can pick any slot 9 spell. For example.
• Meteor Swarm (but max 30 ft radius with Swordmage as point of origin)
• Prismatic Wall (but upto 15 radius sphere, ie 30 diameter sphere, or upto 30x30 wall 30 feet away)
• Foresight
• Invulnerability
• True Polymorph (but "melee range", ie touch or reachable by weapon)
• Shapechange
• Power Word Heal
• Mass Heal (but max 30 ft radius)
There is only one slot 9 per long rest, so whichever spell the player picks is fine, as long as the spells themselves are balanced.
Astral Projection is fine, except any spell that requires a "1 hour" casting time should be a "ritual" − and not a "spell".
Rituals need to disconnect from spells and become a separate design space. Rituals can require anything (level prereq, use of a bonus action, quiet meditation for 8 hours, astronomical timing, special rare ingredient, costly item, strange behavior, or even have no requirement, whatever makes sense for the thematic and power of the ritual). Ideally each ritual lists a specific skill check to determine its success or failure, or crit or fumble! Any class including a Fighter can attempt to perform a ritual, by means of the skill check. Astral Projection is an example of a magical effect that makes more sense as a ritual. A caster has the option of using a spell slot instead of a skill check in order to guarantee success. But most casters will save their slots for combat, and risk skill checks for rituals anyway. Rituals are the kind of magic that happen in reallife fairy tales and in contemporary popculture magic.
Wish should be a feat, including for the Wizard.