What should be the mix of funds for investment of 3 to 5 years

Mutual fund investing should be done based on your risk taking appetite. Once you know your risk taking ability, you can select funds from appropriate categories.

However, considering your age and that you are retired, we can presume that you are a moderate risk taker, therefore, you should invest more in debt and less in equity. To simplify things, you may consider balanced funds and debts fund. These two category of funds would be ideal for your investment horizon of 3-5 years.

Please check the top performing balanced funds from here https://www.advisorkhoj.com/mutual-funds... and debt funds from here https://www.advisorkhoj.com/mutual-funds...

Yes, you can invest without a distributor by approaching to the respective AMCs or visiting their websites and transact online.

Yes, you are right - The return % are net of expenses. Thanks : )