A wick, in addition to the other suggestions, will improve tea light performance by producing faster burn time. The problem with a slow burner is that the pot loses heat even as you heat it, and the rate of heat loss increases with the temperature of the pot. If you heat it too slowly it will reach a temperature at which heat is going out as fast as heat is going in. The wick gives a faster burn by increasing the surface area of the alcohol available to burn.

Just don't use too much wick because it takes up space in the already limited tea light.

You can find larger tea lights that will hold a full ounce. They are the same thin aluminum as the regular votive size.