How do you know that the cycle will be over in 3 days?
The question of what fish is best to start off with is dependent on a lot of things. First, we only know the total volume of your tank, 19 gallons is a rather odd volume, so it is likely that the tank has a 'nontraditional' shape. What are the dimensions of the tank?
Second, we don't know what the water parameters are, and we certainly wouldn't want to recommend fish that aren't suitable for your water.
Lastly, its a matter of taste. We can make suggestions, but you have to make the ultimate decision, because you are the ones to look at them everyday. So, what I may like may not match up with what you like and want to have in your tank.
If you could address these issues, we'll be better able to make some recommendations.