Did you just slide out the existing wick into the existing coil? Or did you replace everything? I ask for two reasons: first the coil determines OHM. Also, I have been wanting to try just replacing the wick and leaving the coil alone, but I didnt think it was possible. Is it?
I don't think you can replace the original vivi coil, the coil is wrapped really tight, the chances of breaking the coil, and making them touch is far too great. Replacing the coil would seem the best way forward.
I would avoid wire with aluminum and iron. This wire has a very small % of iron and may be ok.
The matter of Kanthal vs Nichrome, has long been debated on these forums, as well as health and safety concerns. I'm sure others would point you in the right direction regarding health concerns. We have both Chemists and a variety of Medical/ Health Professionals as members on ECF, if something were untoward we would all be notified rather fast. However this statement is not meant to negate your concern.
As far as affecting taste is concerned, Nichrome and Kanthal have been accused of this, more often caused because the wire has not been prepared (running a lighter over it) before setting the coil. Some say it is only there for the first few few puffs, others are more sensitive to the metallic taste and claim it never leaves, both Kanthal and Nichrome have been accused this.
I prefer to use Kanthal, but Nichrome 80 is commonly used and cheaper too. So long as you know the gauge you want 32 to 36awg are most common sizes used, easy enough to find both on eBay and Amazon, just google it.
If you are after Kanthal this can be found currently on ebay both from Germany and USA link is here:
200' roll of 32 gauge A1 Kanthal resistance wire for use in rebuildable atomizer | eBay