If you want exactly-right avocados, one way is to buy them frozen (Aldi does them) and thaw as much as you need overnight.

My go-to salad has avocado, lettuce or rocket, sweet cherry tomatoes, capers, very finely sliced shallot or if not available, onion but not much, a thick vinaigrette often made with rapeseed oil, Dijon mustard and white wine vinegar shaken the bejasus out of to emulsify it, and a scatter of just-toasted pine nuts. And a sprinkle of either fine-chopped parsley or fine-chopped fresh dill.