By 3.5 rules, persistent spell effects only spells that are personal, or have a fixed range. Displacement has a range of touch, and does not qualify. To that end tho, divine power should be persistable with strength domain, but is not, and I am sure there are other exceptions as well.
Since dispel is already a bit issue here for casters, I dont really see any problem with adjusting the spells to qualify tho. This is a very high magic server with ability scores in the 50 after all.