You have a good point there. To counterbalance that, I had expanded rhe application to any spell that creates or summons undead instead of just shifting from summon monster to summon undead. Its unfortunate that the summon undead line ends on V, a point that makes me wonder as to why, but there are fortunately other means. Now, I could brew VI-IX, and perhaps I will. I've adjusted the features dealing in summoninng, but you are right that the base is purely a summoning PrC and this variant remains one in part.