Felon said:
Let's think this through. Why should conjuration be limited to just summoning solid matter?
Because, in d20, Conjuration spells work with matter?
http://www.d20srd.org/srd/magicOverview/spellDescriptions.htm#conjuration
While the first paragraph does mention summoning energy
Each conjuration spell belongs to one of five subschools. Conjurations bring manifestations of objects, creatures, or some form of energy to you (the summoning subschool)
none of the descriptions of the subschools mention pure energy. They all mention matter and/or creatures.
On the other hand, Evocation specifically mentions manipulating energy:
http://www.d20srd.org/srd/magicOverview/spellDescriptions.htm#evocation
Evocation spells manipulate energy or tap an unseen source of power to produce a desired end. In effect, they create something out of nothing. Many of these spells produce spectacular effects, and evocation spells can deal large amounts of damage.
If a spell is dealing raw energy damage from nothing, by the Rules As Written, it should be Evocation. If it's a Conjuration spell, it should create, manipulate, or retrieve matter which in turn does the damage.
At the very least, a conjuration spell that does direct damage should not have a duration of instantaneous, since
instantaneous means
The spell energy comes and goes the instant the spell is cast, though the consequences might be long-lasting.
.
Having a non magical orb of force laying around after a spell attack seems...odd.
If it had a duration (say, 1 round) then it pops at the end of the round, and is gone. That takes care of most peoples (including myself) objections to the Orb spells (I beileve, based on what I've seen).