I was thinking about giving Beguilers all Sorc/Wiz Enchancement and Illusion spells on their list and changing their Advanced Learning feature to give them Enchantment and Illusion spells from other spell lists (which would include getting some spells to be lower level).
Would that have any change to Beguiler's Tier ranking?
I'm not sure, off the top of my head, which spells that would add to their list.
Similar thing with Warmage. He'd get Evocation and Abjuration spells (note however that it would come together with houseruling Conjuration spells that should obviously be Evocation, I'm looking at you Orb line of spells).
I think adding Evocation and Abjuration would be fine. Are you talking just from the PHB, or all published sources? That can get kind of... big.
Note: They already
have the lesser and normal version of the Orb spells. The reason they're Conjuration instead of Evocation is to justify them having SR: No. The idea is that you are
summoning the element and propelling it at the target, rather than magically evoking the energy. Yes, it's nitpicky, but that's why they don't allow SR.
Dread Necromancer would get Necromancy and Divination spells.
Not sure about what schools to give the Healer.
I added
Stinking Cloud to them, given that they already get
Cloud Kill and
Acid Fog. It seemed like an oversight, and it's nice utility at that level. Especially since their minions are immune.
Giving them Necromancy seems obvious. Divination would go a long way toward making then more powerful, although, they lack the wizards "tool for every job" thing that makes Divination so damn nasty.
No comments on the healer.