I think there are some other important things to find out first.
-Are you interested in maths or science?
-What do you want to be as a uni graduate?
-What do you want to be several years down the track?
-Are you genuinely interested in law?
I had the choice between Comm/Eng and Eng/Law (I didn't think about Comm/Law much as I definitely wanted to do Eng), and I figured that Comm/Eng would compliment eachother more, and more importantly I'm pretty interested in quite a lot of the stuff covered in Commerce, and haven't regretted it since. On the other hand, some of my mates who went into Eng/Law to use up their "VCE Points" aren't enjoying it at all, and are actually looking to swap into Comm/Eng.
In the end it comes down to personal preferences. I think Comm/Eng, Comm/Law, and Comm/Arts will all get you pretty far down the track, so you shouldn't be overly concerned about not being employed or anything after uni

Don't mind the ATAR stuff; that's all to do with the supply and demand for uni spots. This is partially because there is an associated prestige with Law; but there are more positions in Commerce and Engineering faculties, hence they need to drop the ATAR in order to increase the number of students.