I have used halyard hitches on all three of the halyards on my boat rather than splices simply because I reverse the halyards every year.
On the other hand, I splice and stitch the end of my mainsheet to the becket on the first block. If it wears a bit, I can cut a short section off and resplice. the double braid is really quite easy to splice once. You get the knack of it. The right size fid and a pusher is the key.
Three strand dock lines and fender lines are really easy to splice. Some of my lines are extra long for my docking situation, so as they wear or chafe I can shorten them and use in a different location. Obviously, the three strand as pointed out has more give to it.
Another way to use three strand for fender lines or for sail ties is to take it apart and braid it. That makes a flatter lying line that in the case of a sail tie at least can be easily secured with a timber hitch.