Can I just be real with you for a second. Saying you want to spend $15K is ridiculous, and just setting yourself up to be cheated. If you want a system like that, then cool go for it, but don't tell people a number like that. This is like that critical audio. That was basic equipment back in the day, and some idiot athlete had them put it in his car, and bragged about having a $90K system, and it was only a thousand bucks or so worth of equipment.
If you really want to spend that much, you need to find where the professional athletes go to do their stuff. Seriously, if you can find where the Cowboys or Texans players get theirs done, they talk amongst each other, (might be able to search it), that would be a good bet.
The only speakers I can even think of that are priced up there are the Focal Utopias. The problem with doing that is they just don't make sense. You're going for the last bit of clarity that you won't ever be able to notice in an SUV.
* You're going to need $1K+ for sound deadener. Between labor, the size of your vehicle, and you would do not just the mat but also the skin, probably closer to $2k, maybe even a little more. If you're in something like a full size, a tahoe or even a suburban, I could even see $3k for a fully done setup (with labor). Otherwise top of the line equipment doesn't make sense.
* Alternator and battery with wiring, $1K. Depending on subs, you might need a second battery. Big 3 is a little more, could put you about $1500.
* If you want speakers like Utopia, you can use em, but you'll need top of the line amps and high quality cables. You'll only want digital quality audio, HD radio, maybe a hard drive setup to store for that bitrate, or it's not worth it. You can get clear music, but it makes it a little more difficult than just copying it to a flash drive and being done.
* I'm sure you want more than the factory mounting locations. If I had that budget, I would redo speaker placement. Custom made fiberglass door panels alone could be $1K for fully done on the high end, for just one set, once they are fully finished looking great.
If that was me, I'm going with Zapco audiophile series amps. (I'm really limited on my knowledge of top tier stuff though). You might be able to look around and find someone on craigslist or facebook marketplace that does really nice custom fiberglass work.
If you wanted an all out system, you could realistically spend more than half of that $15K budget on not audio equipment. It's certainly a high end budget, but I would still plan this all out before you do it.