Nagas and other "lost" pretenders

[Nerfix]

In Dominions I there is some Pretenders that just aren't wortwhile. Lord of the Nigth, Mother of Lions, Dragons and (from what i have read) Nagas, and "Rainbow Mages" to some extent. What have you done to make these Pretenders worthwhile.
I am also concerned that will the RB Mages become even less usefull, even if their cost has been reduced, because bless effect is now dependant on your starting magic, and it requires minium 4 to get an effect from a magic path.