Dowell needs lots of matches vs proper players to learn how to get round not being that strong and not that quick.
Osman would be the best example here so it might be a couple of years before Dowell is properly ready.
Dowell has a very slight frame but he's still quite tall. Get him on the weights and see if he can get some shoulders.
Alli only has a very slight frame and is similar technically, but he uses his body very well and is aggressive with and without the ball. Think dowell should look at him for inspiration.