I think I'll highlight Dalots career In a few sentences, he has shown he will not improve defensively in my opinion. You cannot as a professional footballer develop qualities overnight that largely require intuition and instincts to succeed. A player needs the talent and then that's where improvement comes into play, you develop what your capable of and Dalot has shown absolutely no talent whatsoever to the defensive side of his game to be a sound defender.
The Everton game alone displayed that, he couldn't read the game, had no awareness not only of movement around him but spacial awareness which is a key. He's also not even shown to be willing to stick a foot in, I know none of us would like to be kicked in the face (potentially) but we are not professionals, we are not paid houses as a weekly wage, you need to put all on the line for 90 mins.
Going forward however it's a completely different story, the revelation that Ole should give him is to move him permanently to a right winger. It suits his strengths, he has skill in possession, can run with the ball and has great execution on a cross a whipped ball is always dangerous for the opposition even if it's inaccurate because the trajectory of the ball causes defences problems, you can atleast get a corner or a mistake.
Dalot should in no way shape or form be considered a right back for the future at this club. Only a winger or a wingback where a centre half can occupy a similar position to cover and double up.