Those balanced OEM systems, have a lot of thought and engineering put into them. signal processing is what makes them sound good. premium systems are tailored specifically to the car they are in by audio engineers with testing equipment. You need signal control to overcome the many variables in the system and environment.
If your truly looking for that balanced sound your going to need a DSP amongst your system and are going to have to learn to use it correctly. you can spend 1000's of dollars on the best speakers and amps and never achieve the sound of a premium sound system without a dsp. there are many available. from rockford, audiocontrol, audison, zapco, alpine etc... lots of learning and tuning to achieve what the premium systems will do.
JBL has one called the MS-8 Its one of only a few that will automatically tune the system to sound balanced and well tuned. Its for those of us who don't have audio engineering degrees or the time to learn it all. I run it and the difference with it is incredible. At least look into it, it might cost you half of your budget but the result will be far better then just spending all the money on speakers and amps.
Toreador Red 05' FX4
4.0 4x4 A/Tran Ext.Cab Daily Driver. Nomads, BFG M/T's
Alpine 9857, JBL MS-8 DSP, US Acoustics 2x80w & 2x100w, Vifa 1" XT25 Dual Ring Radiator Tweeters 3k+ 24db slope, Dayton Audio 7" RS180-4 Mid-woofers 100Hz-3k 24db slope, 500w rms Kenwood Class-D Mono - JBL 10" GTO1014 Sealed. 100Hz- 12db slope