You'll need to look at your overall portfolio to decide what to do. Look at how much you have (how many months worth of expenses are covered for emergencies). Next, look at your needs for additional cash in the next few years. Do you need to replace a car / roof / appliance / pay for a child's tuition / etc? Consider adding that money to this account.
For your short-term goals (<5 years), I'd put my money in a mix of money market, short-term bond funds (treasury and high-grade corporate), and a very small percentage of stocks. I use ETFs for their tax advantages and flexibility (i.e. no minimums).
Marriage is the social union of two individuals that creates kinship. This union of love birds does usually include the union of the finances as well! Most of us are used to the privacy that comes with having our own individual bank accounts and dread anyone else knowing the exact details of our financial statements. Hiding that impulse Chanel or Panerai purchase is indeed important sometimes but do consider some of these merits of having a joint account.