You are far enough into EA to know which companions you like. If you haven't seen any Karlach media (the last Origin character), i would look up a little bit to get an idea of who she is. Based on your favorites, I would pick whichever class compliments them.
i.e. if you plan on having both Karlach and Lae, your Paladin might be overkill on number of frontliners
If you don't want Shadowheart, it might be worthwhile to run your bard so that you have some basic support for your crew.
(Of course you can always multiclass or respec any of them once you have a better idea of how the game feels.)
