I mean there's a million different ways of a Guacamole, salads and sandwiches are always an option. Garnish in soups (tortilla soup with wedges of avocado is to die for) is good. But what more would you suggest?
What spices would go best with it? And is it true that cooking makes them bitter?
Sounds like you are using them just fine! Guacamole, garnish, and as a spread on sandwiches, etc..all great uses. Spices that go well, are usually salt and lime. I would never cook or blend an avocado.