My wife and I have our money structured thus:
- About one month's income in savings at the credit union. This is for spontaneous or very short term things; we dip into it a few times a year.
- A savings fund in the form of index funds in a regular brokerage account. We contributed a little bit each month until it hit a total we were comfortable with and called it good. It's for medium to long term large expenses. We paid for half a car out of it a couple years back, and will use it to put a new roof over the house in a few more hence.
- 529 for the kids.
- Retirement.
Back when we were getting started, we set our savings at relative priorities and contributed to all of the above. It was something like 75% to retirement, 15% to college, then 10% to the short term, until that last bucket hit the amount we wanted. Then we steered it into retirement from there.
Not saying this is what you should do, but I thought I'd present it as a possible model, one that has worked well for us.