I believe an interesting bonus/curse to the unpredictable perk could be unpredictable summoning. When you cast a spell from a certain spell level it can pick any theme of equal power/level.
This would allow to summon stuff from what could be an eyeball, imp, light or a stick. This can also lead to some odd and sticky situations.
Really liking that idea.
Barring a select few themes this would be neat.
It would be cooler if like when you target a reagent and use it with a conjurative focus it adds that summon theme to a list of those you have summoned previously and when you summon without a focus you summon one of those themes you have summoned previously at random.
This sounds awesome. Hope it gets implemented
It would be fun to see the sorceror make a spellcraft check and if he/she fails than the summon would go out of control.
Losing control of your summon should not happen unless a DM is doing such for a specific purpose. The summon theme being random, or partly so as own described might be cool. The current randoms on it aren't particularly random, hells Id be okay with every elemental spell randomly being the wrong element, but that's another story.