"more or less as the whim dictated" ... this is precisely my problem. See, with my limited palate I can barely tell what herbs are in something at all, and I certainly can't usefully distinguish them. I can just about tell if something tastes particularly herby in general, or tastes particularly boring and needed more herbs, but that really is as far as it goes. So I don't have any particular "ooh, I feel in the mood to put in some <foo> today" sorts of whims that I can follow.

When I'm cooking, herbs are something I throw in largely for the benefit of my guests, so I need to know how to get them right without being able to judge them for myself.

In mushroom risotto I'd use a bit of fresh black pepper, maybe a bay leaf for richness, and some thyme (fresh if possible), since the nice woody-smoky flavour goes with mushrooms fairly well. Maybe sprinkle some parsley on top just for garnish, or a dollop of fromage frais or creme fraiche; but as various people have said parsley's pretty powerful so take care. Good stock really is everything in a risotto, but I've had plenty of luck with Knorr powdered stock as well as the concentrated bottled stuff you and I used to use.

...oh, and if you can grate the onion finely (I use the Benriner) and fry it slowly, preferably caramelise it a bit, before you start cooking the risotto, that really helps too; adds a lovely sweetish note.

Well, most herbs don't clash madly with most other herbs or food. And most packaging comes with handy hints on the side like :goes well with chicken. Or with unsubtle titles like: Pork seasoning.

So mostly you can get away with going for: needs more herbs, or OK, it's herby enough. Rosemary is very aromatic though, so be careful how much you use.

I was thinking more whimsical than that. ';Today I like the sound of the word marjoram, so we'll have some of that'