I know I'll get berated for it but try Kris Dhillon's base, just make sure you fry the garlic and ginger, but otherwise follow the recipe exactly. It really is difficult to recommend a base on it's own because you really can't mix and match bases and recipes. Well, you can, but you just aren't assured of the outcome. You will almost certainly always produce an edible BIR style curry, but to get the best you have to match a base with a particular recipe.
You don't believe me? Well think on this. I make bases, some without ginger and tomato, and some with copious ginger and tomato. Can you tell me logically that you could use both of those bases with the same curry recipe and still make a decent curry?