I've been making green curry for years, and it always sucks (It's actually quite sad). I've followed David Thompson, and I've found recipes from other top chefs, and they're all pretty much the same, and the flavour is always very meh compared to what I get at a half-decent Thai restaurant. The general paste recipe: (Blend or Pound)  galangal (1 thumb sized portion) lemongrass lime zest shallots garlic coriander seeds 1 tablespoon cumin seeds 1/2 tablespoon bird-eye peppers * 5 (shrimp paste) (I don't put this in) cilantro stems  For the sauce  Good coconut milk (Arroy-D or Savoy) Thai basil fish sauce kaffir leaves  For the recipe: Cook coconut milk until it cracks, throw in the paste, cook until aromatic, then throw in some water, meat and vegetables, cook to desired tenderness, and when it starts to cool off, top with some shredded Thai basil. Optional add lime leaves and fish sauce. Honestly, I feel like a crazy person. I want to say that the missing flavour is not enough birds-eye green peppers, or not enough of the basil flavour. With the peppers, I've just never been able to do more than 5. I have a pretty high tolerance for heat, but putting them in the paste and then cooking them makes this awful back of the throat heat that adds nothing to the recipe. With basil I find that the raw basil flavour is a little overpowering, but if I cook the basil at all it loses all flavour. 
It's not possible for us to know what flavor you are missing in the green curry paste; your comments in the question about basil and peppers suggest that you may have flavor sensitivities that others do not share. That said, I compared your procedure and ingredient list against Pailin's recipe, and noted the following items in her paste which are missing in yours:  Basil Cilantro stems Makrut lime zest (you're substituting regular lime zest) shrimp paste (I assume the parens mean you're omitting it) around 10 chiles  I'd guess that it's a combination of the items you're omitting that make the paste unsatisfactory, rather than any one of them.  That said, shrimp paste adds a pretty significant glutamate punch to the paste, so if you're omitting that, it could be the key piece. 