Here is my first version,
compared to Pathfinder Spells:
L3 Spell: Advanced Magic Missile, 1 missile at caster L5 (another missile every 3 levels, up to 5 missiles total at L17); each missile: 1d6+3; range doubles
L5 Spell: Greater Magic Missile, 1 missile at caster L9 (another missile every 4 levels, up to 5 missiles total at L25); each missile: 1d8+5; range triples
L7 Spell: Supreme Magic Missile, 1 missile at caster L13 (another missile every 5 levels, up to 5 missiles total at L33); each missile 1d10+7; LONG RANGE
So what does that look like?
Wizard L5
1:MM 3 missiles, 1d4+1 each, range 150 ft (damage range 6-15)
3:AMM 1 missile, 1d6+3 each, range 300 ft (damage range 4-9)
3: Fireball, 5d6, range 600 ft (damage range 5-30) REF/half
Wizard L9
1:MM 5 missiles, 1d4+1 each, range 190 ft (damage range 10-25)
3:AMM 2 missile, 1d6+3 each, range 380 ft (damage range 8-18)
3: Fireball, 9d6, range 760 ft (damage range 9-54) REF/half
5:GMM 1 missile, 1d8+5 each, range 570 ft (damage range 6-13)
5: Cone of Cold, 9d6, range 60 ft cone (damage range 9-54) REF/half (Note: considered an underpowered L5 spell in PF, see here)
5: Lightning Arc, 9d6, range 760 ft (multi <60 ft apart) (damage 9-54) REF/half
Wizard L13
1:MM 5 missiles, 1d4+1 each, range 230 ft (damage range 10-25)
3:AMM 3 missile, 1d6+3 each, range 460 ft (damage range 12-27)
3: Fireball, 10d6, range 920 ft (damage range 10-60) REF/half
5:GMM 2 missiles, 1d8+5 each, range 690 ft (damage range 12-26)
5: Cone of Cold, 13d6, range 60 ft cone (damage range 13-78) REF/half
5: Lightning Arc, 13d6, range 920 ft (multi <60 ft apart) (damage 13-76) REF/half
7:SMM 1 missile, 1d10+7 each, range 920 ft (damage range 8-17)
7: DB Fireball, 13d6, range 920 ft (damage range 13-78) REF/half
Wizard L20
1:MM 5 missiles, 1d4+1 each, range 300 ft (damage range 10-25)
3:AMM 5 missiles, 1d6+3 each, range 600 ft (damage range 20-45)
3: Fireball, 10d6, range 1200 ft (damage range 10-60) REF/half
5:GMM 3 missiles, 1d8+5 each, range 900 ft (damage range 18-39)
5: Cone of Cold, 15d6, range 60 ft cone (damage range 15-90) REF/half
5: Lightning Arc, 15d6, range 1200 ft (multi <60 ft apart) (damage 15-90) REF/half
7:SMM 2 missiles, 1d10+7 each, range 1200 ft (damage range 16-34)
7: DB Fireball, 20d6, range 1200 ft (damage range 20-120) REF/half
Wizard L30
1:MM 5 missiles, 1d4+1 each, range 400 ft (damage range 10-25)
3:AMM 5 missiles, 1d6+3 each, range 800 ft (damage range 20-45)
3: Fireball, 10d6, range 1600 ft (damage range 10-60) REF/half
5:GMM 5 missiles, 1d8+5 each, range 1200 ft (damage range 30-65)
5: Cone of Cold, 15d6, range 60 ft cone (damage range 15-90) REF/half
5: Lightning Arc, 15d6, range 1600 ft (multi <60 ft apart) (damage 15-90) REF/half
7:SMM 4 missiles, 1d10+7 each, range 1600 ft (damage range 32-68)
7: DB Fireball, 20d6, range 1600 ft (damage range 20-120) REF/half
I think this is playable in both 3.5 and Pathfinder.
What do you think about color coding the different levels of Magic Missile? The basic MM would be red. The AMM would be yellow. The GMM would be green, and the SMM would be blue.
Looks like we we're not the first to suggest such changes, See here But I think the suggestions are TOO powerful.