Hot Cocoa --- room for improvement!

Just made the best Hot Cocoa ever!  But still has room for improvement.

1/2 cup splenda
1/4 cup cocoa
1/3 cup water
dash of cinnamon
dash of salt
 - whisk together in saucepan over medium heat
 - stirring constantly to prevent burning

2 cups heavy whipping cream
 - heat 2 cups of heavy whipping cream in microwave for a minute to warm up
 - whisk warm cream into chocolate sauce
 - cook until just starting to boil

2 cups of milk
1 tsp vanilla
 - heat of 2 cups of milk in the microwave for a minute to warm up
 - whisk warm milk into creamy chocolate sauce
 - whisk in vanilla

Drink! 

-----

There are two point that I would like to improve:
1) the after-texture leaves a powdery mouthfeel -> want a creamy afterfeel.
2) it tastes like it was made with artificial sweetener (maybe because it was?!?) -> want the sweetness to balance the bitter of the cocoa, but not the chemical bitterness from the sweetener, but still can not use sugar.

Ideas?