Bad move on the prepared spells.

The Duskblade has more powerful spells, more spell output, spell channeling and more potent effects thanks to Spell Power.

I see no reason why this class shouldn't have spontaneous spellcasting along with it's chosen domain spells in its repertoire, plus domain powers. The Duskblade would still be more powerful, but the skill advantage of the Shrine Warrior would even them up nicely.