Due to the update 9 changes to sorcerer and wizard elemental damage lines the hireling casters are actually missing action points where they previously held a pre-U9 enhancement.

I would suggest one step further when fixing this - that the various prestidge enhancements be applied to some of the classes (not just wiz/sorc) because currently hirelings, by design when introduced, are nearly all vanilla builds and give little flavour to the class summon nor insight into the extended class features for anyone unfamiliar.

Selecting a hireling should also then become easier rather than having to examine what spells they possess and allow you to tailor the summon to the quest undertaken, knowing that it is a fire savant for the frost giants or ice savant for the fire mobs etc.

At the moment the hirelings are all pretty generic and underwhelming in their class - this may be ok for random mediocre quests but right now they are chosen for knowing to possess extended haste or heal spells rather than, say, being wilderness-appropriate like having a cold-based caster for searing heights or Paladin Hunter of the dead in Orchard.

As another example, if the cleric is going to stick close to me I would rather he were a radiant servant as they are invariably unable to keep themselves alive let alone heal me in the thick of action when called from their park point. Having a pale master summon would lessen the wizards likelihood of quaffing potions or being healer-dependant if non-warforged too.

I appreciate some prestidges are going to be too hard to implement/too many hotbar buttons/undesirable in a hireling (asassin for example) but they do need refreshing - spellsinger II for the bards who have level I and angel of vengance for the melee type Favoured souls are recent changes that would be beneficial improvements.

If the summons lasted much longer and subject to a wide variety of quests then a multi-tool would be appropriate but when doing a known quest; wilderness area or a themed chain and using a hireling then he/she being mob-appropriate with a known PRE would be beneficial.

Right now I rarely put a hireling caster into 'attack' mode because I know they are too weak to kill the mob or use a underpowered area spell that won't kill so it's just unwanted aggro leading to their own quick demise - having their enhancements using a prestidge class where I know they will use an effective range of single-target/damage over time boosted elemental spells I might actually use this mode (right now I were rather this button were replaced with something more useful as the toolbar space is limited)

Side note: The Compendium is lacking the Bard; Favoured soul and rogue hirelings:
http://compendium.ddo.com/wiki/Category:Hirelings