I'm sorry to hear that you're not enjoying Literature! I think it's a good idea to change if you really hate the subject - mainstream English is broader in scope so if you really don't like the in-depth analysis of Literature, you might enjoy English a bit more.
The big difference is the new AOS called Crafting/Creating Texts - there you're not required to analyse anything, but you do need to produce a text (any kind of prose) about an idea that your school chooses (here are our blog posts about this AOS). And of course the Argument Analysis, where you have to identify a persuasive text's arguments and the mechanics of persuasion used.
I wouldn't suggest worrying too much about scaling aspect of either subject - it's not a huge difference (last year it was scaled up and down by about 1-2). What's more important is whether you enjoy the subject enough to put in the effort to study!
