I think that English Language is worthwhile, if not- better than mainstream English (and probably literature), though maybe about half the state might disagree with me..
I have heard that EL is more suited for analytical people who are proficient at mathematics and/or sciences, whereas English is simply better for creative people who read to a frequent extent
That being said, EL is a difficult subject with a bad or clueless teacher (trust me on this) so if your teacher isn't giving you enough information or accurate information, you need to get a tutor, unless your textbook pretty much tells you everything and you can understand 'everything' perfectly
For Unit one and two, half of my SACs were in test format where a small text would be given for various questions, and you'd have to answer accordingly to that text, and the other half were in essay format
The essay writing for EL is quite different to English, as your assessors are simply looking for content and proof of knowledge whereas for English, they are looking at how well you present your information, and how creatively you do so
In which suburb do you live in? I know of a few tutors : )
P.S, It isn't important to excel or do exceptionally well in units one and two because you relearn everything to a deeper extent in unit three and four, though it would really make your Unit three and four much easier to learn from if you paid attention in Units one and two.. I got 45%'s for last year's grammar SAC (first SAC of the year) and this year for unit three, I ranked amongst the high end for my grammar SAC..