What details are important to choose ROM

[Blue Sky]

Hello;
How do you choose ROM for your mobile?
what specifications are important to follow?

I mean there should be some rules to follow to choose the correct one that matches your phone, other than Makes and Models.
CPU?, graphic card? modem? baseband? Kernel? OS? All of them.
I understand different hardware means having a correct driver for it,
is there a way to right the correct one the later on fix some issues.

if anyone can point me to the right direction I appreciate it.
I have a Clone samsung Galaxy S4 I9500
but when I look for custom ROM, some of the specification on the ROM are different than what I have, so I am not sure what part is REALLy IMPORTANT to follow,

Here is the specification of my Mobile which I got from MTK Tool Ver. 2.5.3:

Hardware: MT6577 ( universal 5410 is Fake)
Model: S4
Build number: ALPS.ICS2.V1.3
Build Date: 20130911-023426
Android: 4.2.2
Baseband v: MAUI.11AMD.W12.22.SP.V7.P3.2013/05/11

Kernel v: 3.0.13 (root@yc-desktop)(gcc version 4.4.3(GCC)#10SMP Wed Sep 25 09:48:20 CST 2013

Uboot Build v: should be root shell
LCD driver IC: should be root shell
Free space: system- 124.0M; data- 415.4M; sdcard- 1.9G; C:\ 204503M

==============

and info from CPU-Z app:

Samsung Exynos Octa 5410 1.89 Ghz

cpu Architecture:
ARM cortx -A15 +ARM Cortex -A7

revision: r3p0
process: 28 nm
clock speed: 384 Mhz- 1.89 Ghz
Cpu 0 1001 Mhz
cpu Renderer: Power VR SGX 531

Display: JDQ39.I9500ZHUAMDE
Hardware: mt6577
Android version: 4.2.2
OpenGL ES version: 2.0
Kernel Architecture: arm71
Kernel Version: 3.0.13 (eng. root.1378866812)
screen resolution id dp: 320 * 533
screen Density: 240 dpi
Total RAM: 1790 MB
Available RAM: 474 MB
Internal Storage: 0.49 GB
Available Storage: 0.36 GB
Root access: Yes
voltage: 4304 mV
=============

appreciate your help

[cookiedough]

The ROM must be for your specific model phone. If it's not, it's almost guaranteed not to work. For phones like Galaxy clones, there are going to be many different ones out there.

However, it is sometimes possible to PORT a ROM from a phone with similar hardware.

[Blue Sky]

thanks for your reply,
but I don't know any to try, I know it is difficult to find.