EE2 I don't know about, but I can tell you now, ME2 is awesome.
It's probably the only subject in the HSC which is intellectually stimulating. And if you're even half-decent at it, scaling is lovely. Not that it should be about scaling.
There's a few things I'd change if I were to do the HSC again. I would stick with my decision to do 4u.
Are you doing Latin Extension?
Anyway, art+latin+EE2+ME2 is 12 units. If you can handle it, that's fine, but there's certainly nothing wrong with 10 or 11 units (I do 10, since only 10 will be counted). You need a minimum of 4 subjects, so latin and art are locked in.
EE2 scales lower than ME1 and ME2 (though it still scales very high). But EE2 and EE1 are also only 1unit subjects, unlike ME2 and ME1 (the latter only if you do ME2). In the case of maths, if you do 4unit, Advanced is excluded. In the case of English, if you do 4unit, Advanced still counts. About 30% of students each year get an E4 in ME2 (equivalent to a band 6).
Doing ME2/EE2 simultaneously could be a problem (but not necessarily). ME2 is hard work. But then, so is doing a good solid major work. Some people end up spending too much time on one and not enough on the other.
I was considering EE1 and 2 for year 12 along with ME2, but decided against it simply because it meant I wouldn't have to do needless extra work.
Oh, and one last thing: if you hate maths, taking 4unit is probably not a good idea. It's also not a good idea to take a subject because your parents tell you to.