I know. I know there are so many spells that we all would like to see added but many just aren't feasible for DDO.
There are quite a few that could be added though.
Protection from Chaos/Evil/Good/Law - Sor1/Wiz1/Clr1: Since we already have Protection from Evil it would seem easy enough to add the others. It could be like the Resist elements spells as a single spell that brings up the different choices to cast.
Gaseous Form - Sor3/Wiz3/Brd3: The game movement would be the same as being dead, so that shouldn't be too difficult to implement. And like invisibility it could be ended by any action. Vulnerability to Air Elementals and incorporeal creatures would have to be added though.