1 more option for each level of summon spell would be great. (but i'll add 2 for completeness, a neutral option)
Wizards and sorcs can summon all types. Clerics are limited by alignment.
Melee(tank or dps) and Ranged(caster or missile) summon for each level would be the best.
1) Fiendish Rat (Evil) dps /control via disease
Giant Fire Beetle (Neutral) ranged firebolt
Celestial Dog (good) tank
2) Fiendish Scorpion (Evil) (dps/control via poison)
Bombadeir Beetle (Neutral) Ranged Acid
Celestial Lion (good) (control) ( Improved trips a lot)
3) Hellhound (evil) ranged dps
Small Ice Mephit (Neutral) melee dps
Celestial Bear (good) tank
4) Fiendish Spider (Evil) ranged control
Normal Mephit(sand) (neutral)
Lantern Archon (good) ranged nimbus of light
5) Elemental - Earth (neutral) Ranged Control
Shadow Mastiff (evil) Melee/Control
Hound Archon (good) Melee Dps
6) fiendish troll (Evil) melee dps
Janni (earth djinn) (Neutral)
Bralani (good) Ranged Healing
7) Efreeti (Evil) ranged dps (fire spells)
Invisible Stalker (neutral)
Genie (Good) control (air spells) (ball lightning, whirlwind form, greater command)
8) Bezekira (Evil) tank/ dps
Greater Elemental (fire)
Lillend (good)
9) Hezrou (Evill) dps
Elder Elemental -water
Planetar/Archon (good) control (or storm giant)
For sorcs and wizards you can choose either form regardless.
Clerics only get one form or the other based on their moral alignment axis: Neutral or Good