Much like Loras (and others) have said, most of our feedback is not meant to force you to take a path that makes you uncomfortable. However, any concept has original takes that is in your interest to consider from a critical point of view. In role-play there is no “this has to be right, this instead has to be wrong” but it is important to have an organic vision of your character and know how it connects with the existing lore and setting.
Well. Using fel would very much be seen as a betrayal for all what the kaldorei stand for. Up until recent times, I don’t see a way in which a fel user would be welcome in the traditional night elf society. Fel magic is deeply despised and for a good reason: to use fel magic a caster has to drain life and souls. It’s a very wicked form of magic. Most kaldorei, who are in sync with nature, won’t like that.
I think a non-demon hunter night elf which uses fel to emulate Illidan’s teachings, but yet remains in close contact with his kaldorei family can’t be done. Fel is a big no-no to them. And even arcane magic was outlawed by Malfurion after the War of the Ancients…
So, let’s imagine that your character is a spellblade, even if he decided to use arcane magic, which is far less dangerous as a source of power, he would have been tolerated (and likely frowned upon) only after the Cataclysm, when the highborne of Eldre’Thalas were introduced. Before? Very much an attack on sight!
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My next question would be, why keep Illidan as a father-figure/reference? It’s not wrong but it feels unnecessary, seeing as a spellblade would be tied to the Kaldorei Empire’s tradition. If we go with the idea that your character isn’t a demon hunter anymore, why keep a background connected with Illidan’s ideals, only for your character to reject said ideals right away?
• Some ideas for the Spellblade thing below:
He could be related to the highborne of Eldre’Thalas. He was exiled with them, but introduced back to society as of the Cataclysm. Or if that’s not your thing, perhaps a young warrior seeking to mix his sword skills with magic, learning from the highborne after they were introduced to society?
Perhaps they lost someone dear to them as the Burning Legion invaded, and decided to reach out for a night elf that could empower his weapons with magic. Then, he decided to do it on his own, and combined magic with weapons. I’m just tossing out ideas…
But if you want to keep a demon hunter vibe instead.
Keep some of the edge: demon hunters have a very tragic backstory on average!
Retain the spectral sight (ie. use a blindfold to cover the eye), use demonic magic, apply it to your weapons etc (but you don’t have to go as far as using a metamorphosis and exploding with fel novas).
As a result, you’re not likely to be very loved by your night elf comrades, who will look at you with distrust, but you can use more standard clothes and go around without horns.
(Ie. Look at classic demon hunters, like Loramus Thalipedes).