LordTobiothan
Crypt Horror
Shes not a one trick pony - as I said being a loremaster in shadow is a big deal if you're playing end times magic. Shes quite the beast of a caster being able to fly to where she needs to be and blast with magic. Unfortunately this leaves her quite vulnerable having basically no saves whatsoever.
Against shooting lists you have to hope for first turn and fly somewhere you aren't goign to die before being able to engage. At least she has that opportunity; Arkhan and Mannfred aren't as safe in combat so they are going to be vulnerable all day long and you'll likely watch them die more often than not. At least Mannfred can heal himself and has 5+; Arkhan is just waiting to be blown off the table. Arkhan might be 1/3 less costly than Nagash, but Nagash can take twice as many wounds, likely much more with the ability to heal himself.
In combat, she will win. That's a one hell of a nice trick for your pony. The only way she wont win is maybe against a 3++ re-rolling cheese ward. Still, you have plenty of time to go to town on vamp spells and negate any wounds that made it through to her so at the very least shell pin down some unkillable super lord for the whole game while blasting some of the worst hexes around unhindered.
I'm wondering how long the end times magic will last for. Its fun now but there too many unanswered questions like, should mages really be getting loremaster in 2+ lores at once? How does a power scroll even work now? If Nef is even still around in 9th edition, she may lose a lot of her potency as she is now. But with the end times in full swing, its a great time to get her on the table and freak out your opponents with her surprisingly nightmarish magic and unstoppable melee.
Most people don't want to play end time magic and no current tournaments are allowing it. So any benefits assumed through abusing those shitty rules won't really help your argument. I personally think she lacks combat ability compared to her stickiness.