To me Golden Monkey is more on the side of sweet and less on the side of sour, unlike the classic Belgian Tripels I have tried. I know this is seen as a "flaw," but I happen to love it. Does your grain bill and yeast combination provide this flavor profile?
I also like the fact that Golden Monkey is a bit "spicy." I'm guessing the yeast and coriander should provide this?
Wow, I've made and drunk a lot of tripels and never thought of them as sour! Do you Westmalle to taste like that?
At any rate, the aromatic and biscuit malt, in conjunction with the yeast, provide that sweetness. The yeast and coriander take care of the spiciness with the coriander providing a bit of citrus also.