When you multiclass spellcasters, do you get additional spells from having a high ability score from all of the classes? So, for example, let's say I have a cleric 1/druid 1/wizard 1, and I have a 16 wisdom and a 15 intelligence, do I get 2 wizard spells, 2 druid spells, and 2 cleric spells (plus the domain spell) for a total of 6 (7) 1st level spells?
Yes, you do get the bonus spells for each class. On the other hand, you're also casting as a cleric 1/druid 1/wizard 1 rather than a cleric 3 or druid 3 or wizard 3.