I've got the Same situation here mate ,made the transition more than two weeks ago , with mixed feelings , but the perfectly huge size is what's keeping me with this baby.
I haven't messed about with ICS yet ,but I know there are problems with loosing root when switching ICS ROMs
Something about ICS repaks as well....
and while I'm a noob no longer , I really don't view myself as an expert on custom ROMs either , especially ICS ROMs , so you should ask someone else about this.
but my info goes like this:
1.you need to flash abyssnote 4.2 kernel as it has red pill recovery which is needed to flash ICS ROMs
2.from there you should wipe everything ,factory reset ,cache ,dalvik.
4.flash an ICS ROM and that's it.
4.Pray you still have root
Hope I helped and sorry for not providing links as I'm on my mobile browser.
EDIT: here is a link for you , even though you already have an ICS ROM ,I think you'll find some interesting info there
EDIT2: Could you check one thing for me since you're on ICS , could you check if ICS supports RTL (Arabic) character shaping by default? Thanks