Lowering Spell Level in 3.5/Pathfinder

[g3taso]

I have a 5th level spell I want to lower to a 4th level spell. In Pathfinder, there is a feat called Languid Spell (http://www.d20pfsrd.com/feats/3rd-party-feats/rogue-genius-games/metamagic-feats/languid-spell-metamagic) which lets me cast a spell as a lower level spell, with the provision that the spell must have a save to negate or save or half. Using a PF Disintegrate as an example (a 6th level spell), I could cast it as a 4th level spell albeit with the difficulty to resist being 10+Caster Stat and not with the level of the spell added.

How else might I lower a spell to a lower level?

[Diarmuid]

I think this is what Earth Spell and Sanctum Spell normally do, iirc.

[Eldaran]

I'm not sure I trust the designers of a 3rd party feat who think bards prepare spells.

[Ruethgar]

PF has the Whispering Way which can let you learn a spell two levels lower than normal but it causes a negative level. If you can get a spell pool then you have a very good chance of being able to cherry pick them without the Whispering Way reputation. Also effects that give you spells can arguably bypass the rep req so Magical Affinity and Precocious Apprentice are quite nice.

Endurance, Enduring Life and Lasting Life make the casting of these spells still useful, though obviously Necropolitan would be better. It would add an interesting dynamic to the world if the undead were all the most powerful casters. It would also potentially make spellcasting wights a prevalent and terrifying force in the world.