Extemporaneous Spellsinging - Basic Effect

I'm sure I'm being obtuse, but:

The Basic Effect clause in Extemporaneous Spellsinging is meant to be the exact Base Effect from the PC?

How strict ought that be treated? Some are more related than others, and the costs are 'paid for' by the spell building system...

Blast, for example - are you limited to an 1d6/lvl effect if you have Fireball, or can you do a 1d8/lvl? 

Healing - can Cure Light Wounds allow a Cure Critical extemporaneously? 

Presumably Blindness doesn't let you extemporaneate Deafness? Enchantment seems pretty clear. Detect seems to not lend itself to a wide range...Protection is also a lot of gradiated choices from a grouped theme.

If I were to want to simplify, I'd take a shot that looks like:

  • Blast
    • Any Base Damage
    • Extra Physical Effects  (nauseating, gusting)
  • Death
    • Held Helpless
    • Temp. or Perm. Drain
    • Mortal Wound or Slain
    • Disintegrated
    • Any Plain Damage (maybe this is included in all the others)
    • Necromantic Effects
  • Detection
    • Supernatural Effects
      • Ritual Magic, Invisible, Magic, Charm, Curse, Undead
    • Mundane Objects
      • Known Object, Poison, Treasure, Secret Door, Trap
    • Vague Concepts
      • Evil, Good, Danger
  • Enchantment
    • As listed, probably, but I could see maybe 3 or 4 categories
  • Healing
    • Cure/Cause Damage
    • Traumas seperated as listed
  • Illusion
    • Sensory Illusions
    • Cloaking Illusions (inc. mirror image)
    • Phantasmal Killer (which is a weird thing anyway, more of an enchantment, but, hey, history)
  • Movement
    • Movement and Attack Routine Doubling
    • Climb wall, walk on water
    • Flying, or Caster Floating Creature (telekinesis vs other or self)
    • Teleporting
  • Protection
    • Categories as listed - Armor, Enhancments, etc...
  • Summoning
    • One single effect.
  • Transmogrification
    • Statue
    • Living Creature ("gain new form's" included)
    • Undead Creature ("gain new form's" included)
    • Enhancing Transformations (current form gains values 10-20)
    • Physical Transformations (current form grows/becomes)
    • Qualitative Transformations (current form gains values 40+
  • Wall
    • Attacks creatures, does damage, or mortal wounds  (impermeability options included)
    • Causes spell-like effect (impermeability options included)