Using Thomas’ excellent point conversions as a guide, and his inspiration, I whipped yet up an alternative necromancer idea.
Swap out all of the special abilities Thomas mentioned, and replace with:
Lvl 1: Dark Soul -16 cpe
Inexorable 16 cpe
Flesh Runes 48 cpe
Inhumanity 1 (-1 to reactions, +1 to undead reactions) 0 cpe
Lvl 2: Secrets of the Dark Arts 13 cpe
Lvl 5: Necromantic Research 30 cpe
(note: no potions or scrolls)
Lvl 8: Across the Veil 21 cpe
(a lesser transformation into undead, equivalent to Wholeness of Body, Divine health, Longevity and Inhumanity 2)
Lvl 9: Sanctum & Construct Dungeon as mage 3 cpe
(note: no magic items)
Lvl 13: After the flesh 2 cpe
For 117 cpe, as described by Thomas.
This could probably be optimized with other swaps and things, but I think it more or less does what I think of when I think necromancer