I know your DH gets paid monthly, but paying it weekly does help reduce the interest charged to you as it is charged DAILY on the balance, so the more often you pay, the better off you are.
DH and I also have an offset which helps reduce the interest payments. We are with BankWest (noticed you are in WA but not sure if you bank with them) and we have a really simple home loan with an unlimited re-draw facility and quite a low interest rate. We didn't have to re-finance to link an offset account to it, so it might be worth finding out if you can. Any amount of money in that savings account will help reduce your mortagage payment too.
With your DD's account, I have a bankwest kids account (with 10% interest or something) can't remember the name of the actual product, but maybe if you look at getting her a higher earning interest account, you can then deposit LESS into it per month. DS's only requires you to deposit a minimum of $25 per month (which I do) or a maximum of $250 per month. I keep it at the minimum and if anyone gives him dosh for b-day or Xmas then I bank it. I also bank the coins I get into it.
If your mortgage is unlimited re-draw, then you can also pay EVERYTHING earned into it (rather than split into another separate savings account) reap the reward of less interest because of it, and pay bills out of it. We did this prior to having the offset account.
The excess in your home loan is basicall savings which you can take out at any time, but it will be helping to contribute to reducing your mortgage at the same time.
