There's no such thing as 'end game' in this hobby, something your wallet will find out over time....
The 500 are imo good cans if you like a headphone that's a little on the warm side with a slightly forward middle, absolutely glorious midrange, among the best there is imo. If you listen to vocal, smal classic ensemble,jazz or blues you can't go wrong. Only real drawback for me is that it doesn't bring ultimate clarity compared with cans like the HE-6 or HD-800, both of which I also own. And it requires a reasonably powerful amp. For the amps you listed, I own the V200 and have auditioned the Burson conductor, not the soloist. Sound-wise the soloist might work very well with the 500, with more neutral/analytical phones I found the Burson amps a bit too analytical/bordering on harsh. But chef te power on the soloist, I don't know about that.
I own the V200, it's certainly powerful enough and a good amp but a little bit on the warm side (not overly so, don't worry) and not extremely resolving. That last aspect is its only defect to my ears. For the Vio you should know that they will be bringing out new (and more expensive) models that will overtake the 200 (it's an ageing design). So whatever you do, don't purchase one new now, some used ones in very good condition and at a lower price are/will be hitting the market. I heard an ember just once so not really enough to say anything about it but didn't really like it then. Also heard the Schiit and I know the brand has lots of followers/fans but I'm not one of them. Some of the audio-yd amps get very good reviews and are attractively priced but haven't heard them, certainly powerful enough for the 500.
Good luck!
Hope this helps a little.