Spice combination(s) excluding salt, oil/butter, sugar, msg, vinegar, onion/garlic/alliums?
There is the French quatre épices (four spices): pepper, cloves, nutmeg and ginger. And of course you can go crazy with the herbs: parsley, basil, rosemary, sage.
French again: bouquet garni, look it up here.

Let me just add something about the MSG: monosodium glutamate is practically everywhere (tomatoes, cheese, seaweed, ...), not just in Chinese cuisine or soy sauce. If you really cannot eat MSG, your choices are going to be extremely limited. Read more here.

Broadening the field of your question, you could look into culinary traditions that, for religious or philosophical reasons, eschew those ingredients. Some Indian cuisines might help you here, but I am definitely not an expert.