Not really, they mean totally different things to different generations etc. and to add to that depending on your app and system they render completely differen

Not really, they mean totally different things to different generations etc. and to add to that depending on your app and system they render completely different as to change the entire meaning. And that is before taking into account totally arbitrary shortcuts and meanings are introduced in various communities. As a communication tool within a tight group, sure. But outside that emojis are pretty darn bad. Unless you stick to the subset that pretty closely maps to ascii smileys.