I think either player 1 or 2 could go (in that order). I think these two guys would be a more lucrative option, as people will be looking at trainees they can craft from the younger age.
I think even though player 3 is older and not going to make your NT (not the only way to have a great player), he could still be a great value to your team as a keeper. You could craft him to be a good combo starter/ back up.
As to whether he will be slow at inside skills... yes, but that being said, he is going to be your second priority, so just bringing him along slowly isn't going to be that much of a problem (but will test your patience)
I know others will disagree with me on this, but if it was my situation, this is what I would do. Sell those other two guys off (1 & 2) put the cash into my Arena, Train up the HOF in secondaries all season long, with a few primaries, and look for complimentary trainees along the way to add if the perfect guy/s come along.