How would reducing the amount of butter affect the lemon curd? I just made the recipe using one less tablespoon of butter and a scant half-cup of...

rachel, decrease the butter or up the lemon. My suggestion is the latter and , as your very first step, grind in a mini processor the sugar and lemon zest. this works well to get the sugar infused w/ lemon.Since your sugar lemon mixture is going to be heated anyway, grind the 2 together til they get to a syrup. I would double the lemon zest as well. I used this technique in my Lemon Almond Cornmeal Diamonds:
http://food52.com/recipes/15709-lemon-almond-cornmeal-diamonds

Also consider adding more lemon zest at the end. It can make a real difference.

I've never used whole eggs in lemon curs, just yolks. That said, the role that butter plays is essential. It certainly helps the finished produce set up under refrigeration. As well, it is a perfect conveyor of flavor. As for boosting the lemon flavor, I'd suggest increasing the salt a bit, perhaps a half teaspoon. Please bear in mind that the cold flavor will differ from the warm, so feel free to tweak the salt and sugars accordingly.