You will be extremely hard pressed to find components (mids and highs) that will handle 250W, even ones that will really hang with 150 puts you into a very limited pool from which to select.
There is no reason apart from brand loyalty or cosmetics to use multiple sub amps to get up to 2000W these days. Gain matching is going to require more fuckery on your end and is almost never going to be 100% accurate.
You need to take a step back and discuss what vehicle you have, what you're trying to accomplish, how much space you're willing to give up, how much work you can or will do yourself and how much money you want to throw at this.