On the one hand, you really need both a wizard and a druid to prove/disprove the value of the houserule (the wizard because it is, in theory, impacted by the houserule and the druid because it isn't much).
On the other hand, having these characters in the party will ruin the monk/rogue test as the wizard, druid and cleric can handle all the encounters while the monks and rogues run around pretending to be useful.
What a conundrum. Only [MENTION=6676235]Visigani[/MENTION] can save us.
There will be arcane/divine spellcasting via PrCs I expect. However, they will be stunted enough that it's unlikely they will dominate play via arcane/divine spellcasting.