NE-6 is good for the budget. You could instead look at M2 - though both, I suppose are concentrated on the mids and bass.
But, since you are not looking for a stereo setup and would listen through this IEM for all sorts of music, I’d say at least go for RE-0. I see no point in stretching the budget and settling for something less. You would, IMO, need a sort of an all rounder.
TripleFi.10 is above your budget. This was one of the IEMs I was interested in ever since the early days, but never got to it because of the price as well as the fear of fit.
RE-0 would go with most music, not electronica / trance - I suppose. But try it once (after a burn-in of 30-50 hrs) and you will love the level of detail this one brings. It is hard to drive, has more of a mid-bass hump, has microphonics. But even with this “faults”, within $100, it is one of the better IEMs out there.
Phonak PFE is not commonly recommended (may be because not many have it?). When I think of PFE (I have 111 v0, not the latest version), I think “balanced”. It’s neither too forward, nor recessed - just there - enough for my liking. There are no microphonics at all. Again another analytical IEM like RE-0. It does not need an amp most of the time. Though it’s bass is lesser they say, with a good seal at times, I feel it has enough bass and quality one at that. But, with my ears, getting a good seal all the time is not possible.
I’d say you can look at RE-252 instead of RE-ZERO. RE-ZERO for $20 more than RE-0 makes it easier to drive, but I wonder how much of RE-0’s famed highs was sacrificed. If it’s not too much, then it’s a decent choice to consider with it’s bit more bass and may be slightly better build quality. It’s balanced plug and the need to use an adapter to connect is a slight turn-off for me. May be HiFiMan XYZ player would come out with Balanced outs if they end up “upgrading” RE-252 the same way 
RE-252, as far as I’ve read, seems to have a bit of everything and is at the upper end of your stretched budget - $199 + $10 shipping from Head-Direct.
Another choice would be Hippo Pearl ($43 + free shipping from Jaben). Though for me it does not trounce PFE or RE-0, it still plays balanced with good amount of bass. Since I’ve not listened to it so much, I am still not able to put my finger on why I don’t think of it in the same league as PFE/RE0. Audio memory is illusive, but with that - it may be in the highs and a bit less resolution. But they have been used like 10 hrs, so will hold my thought on that. It may suit your purpose.
None of the IEMs I have listed have a wide sound stage, more like normal (except for RE-252? Because I’ve not tried it)