An alternative that would give you more flexibility would be Commerce/Science with a concurrent Diploma of Language Studies. It's five years long, but I think the extra year is worth it for the flexibility and extra study options it gives you. For the Diploma, USYD are offering an intensive pathway starting from next year where you can complete the diploma in one year without it disrupting your studies. This will only be offered for Spanish, Japanese, Indonesian and Korean, but it will allow you to study a language without having to forfeit any units in your study program each semester to study it. Or you can do the Diploma part time and do one unit per semester on top of your existing workload (this would mean you have a choice of more languages and can study it in more depth, but the trade off is that you'd be doing more than the standard semester workload, so only do this if you feel confident you can handle it). I'll actually be doing the latter option starting from next year.