I didn't do ACTL but I'd probably go FINS1613 being hardest, then ACCT1511, then ECON1102 (i.e. easiest).
To me, FINS1613 was substantially different to 1612 which was a piece of cake- 1613 actually introduced some concepts which required you to think rather than regurgitate. ACCT1511 can be easy for some and hard for others- but it depends on who your lecturer/tutor is. My tutor was useless and cried which meant learning just wasn't really an option- and would also explain why it took me many years to catch up and teach myself cash flow statements (it's even harder when you need to talk to clients about it!) and ECON1102 is just HSC economics with a bit more thought required.