Flavoured Black Teas

Hey everyone, seeking advice from my fellow Steepsters who are more experienced flavoured tea drinkers – so far my experience with flavoured teas has not been enjoyable or exciting, with the flavour profile being overly watery, flat and weak in terms of taste. Whenever I visit my local tea store, they often offer flavoured teas with added milk, honey, etc. to try and they taste pretty great! Just wondering if anyone can suggest some general pointers when preparing flavoured black teas (e.g. ratio of water to milk, steeping time, etc.) – much appreciated, thanks in advance!