Right, but without a proper DSDT, the problems you're seeing with the graphic card (which is enabled most-likely from GraphicsEnabler=yes) are likely due to the lack of a DSDT translating the BIOS code to your hardware correctly.
Even if the hardware components are identical, the BIOS is the problem, since Macs use EFI. So a DSDT translates the incompatible code into what OSX can understand, then everything works as it should.
Also, not using kexts could be a bad thing- just like I can install Windows on a bare system and most stuff will appear to work right after the install. But we all know that things only actually work CORRECTLY when the proper drivers (many third party) are installed. Similar with OSX: OOB often works in a basic sense, but a kext (driver) may actually work better.
[EDIT: I see that you installed a 'package' so I'm assuming you used something like the Lifehacker method? If so, that probably installed most of the needed kexts in the Extra folder and mkext file.]
By the way, for mostly cosmetic things like the CPU reading properly, search Google for AboutthisMac.zip and try running it. Usually, it corrects the CPU reading- but it's just a cosmetic detail. If you really want to be sure your RAM, CPU, GPU etc. are truly recognized and used by the system correctly, it's a combination of DSDT and SMBIOS tweaks. There's tons of info on the web about it if you're truly interested. Otherwise, if performance is good enough for you, then enjoy.
One thing I'd advise- make yourself a backup install on a 2nd partition or drive. I can't emphasize this enough. It'll 'cost' you 20GB or so of space, but if you screw with the backup rather than the main install, and render it unbootable- hey, it's just a back up and your main install is fine and there's no starting over each time. If whatever you tests works on the backup, you know its safe to apply to the main. Likewise, If something does screw up your main install, you can always get back into it from the backup, and so on.
To me, it's insanity to run a Hackintosh with only one bootable OSX partition, but if you enjoy living dangerously...