In that order, top is the first i recommend you to try.
MiniCM7 2.2.2 or 2.2.1
I'm using minicm7 2.2.2 and 188.8.131.52 naa 06 unified kernel, it is fast, only thing that it doesn't working is the bluetooth for me, it finds the device but fails to pair. Still, tethering, wifi, usb, everything else works and it is light, you got plenty of internal space, if you use supercharger on it, also gets lightning fast.
If you can't find 2.2.2 use 2.2.1 on 184.108.40.206 naa 14 kernel difference between 2.2.2 and 2.2.1 is that 2.2.2 is compatible with the newer kernel.
How to make minicm7 more light.
Open the zip, remove cm wallpapers, remove cm live wallpapers, remove adw launcher if you not using it and put holo launcher on it's place.
Remove the themes, leave only standard one or put one that you will use.
That will save you several mb after installation.
Put your phone processes on higher priority, look for tutorials around how to set commands on boot or schedule them.
Find tutorial how to install supercharger v6 and follow the instructions carefully.
Don't forget to make backups when you experimenting with those things.
I got gapps installed, gmail, gplus, twitter, quickpic, hangouts, youtube, google maps, voice search, htc ime mod keyboard, ics clock widget, holo launcher pro and street view, also some other stuff like google car home or whatever that was and everything goes in internal memory and i still got 30mb free. ;D
Delneshin 7.0.3 or 7.04 ultra version
Still being worked on, which means supported and that is good as others don't get updates now.
It is odexed, saves internal space, it is fast and compatible with plenty of kernels, also uses supercharger v6 for speed as well which works very good.
FroyoPro v2.5 - Recommend you this one
It is based on CM6, thats the most light rom you will ever find for your x8, it has plenty of cm7 features backported, so it is better than standard cm6 and it is faster than cm7 also smaller if you need space.
Screenshots are from minicm7.