First off: I'll have to apologize for coming into this with some ignorance, for not having read or looked into the source material before this.
Thanks for pointing out the name stuff with the Magician and Healer heroes. The MC because I wouldn't have picked up the reference, and Flare's because LHT has been translating her original name as Freya rather than Flare. I also didn't realize that all the names in this series were given name first.
Not realizing that stuff had me wondering why some of the Heroes had characteristic names (Bullet, Hawkeye) while Freya and Norn had mytholigcal names, and Keyaru wasn't even a name I remembered, let alone connecting it to anything. I still can't really draw such a connection with the names of the beast girl Setsuna or the blade goddess Kureha, but that also might just be from not knowing Japanese, or at least not being intimately familiar with it. On the other hand, for the series' target audience, I'm sure these connections were are simple for them to notice. Going further, the connection with Iblis should be easy for them to see, and the name of the current demon king Hakuou also seems like it's a characteristic name for them.
Some of these seem to translate well, some not so much. With Iblis/Eve Reese...in Japanese you still get a perfectly pronouncable name, while still having the connection to the reference. Trying to set that to English, you can get a reasonable looking and sounding name "Eve Reese" that only bears phonetic resemblence to the reference, you can use the name "Iblis"/"Ibris" and lose the first/last name split and related nuances, or you could try sticking closer to the source and end up with "Ib-chan of the Lis/Ris family" which looks....weird, but I'm not sure if I'm just being biased at this point.
Keyaru....now that you've mentioned where his name comes from, I would actually prefer a name closer to Cure/Curaga, or closer to some other related reference. The "characteristic name" trend across the heroes gets oddly broken up when the first two heroes introduced don't have names that succinctly characterize their heroic disposition (in the LHT translation, at least).
.....and I'm just now finally realizing that Norn never actually was a hero, was she?