I like this kid a lot! To be fair I would go for him but also for De Ligt. De Ligt has truly great potential while Lenglet will only be a third CB option and nothing more.
Yes, De Jong and De Ligt both have that X-factor; hope we sign both and bring in Thiago and Arthur; We just lost Iniesta and with Gomes and maybe D. Suarez set to leave, would make room for all 4, since De Jong can play everywhere from CB-->DM-->CM, Arthur can cover the central midfield and Thiago can play anywhere as CM/AM (both right and left side).
Rakitic to be given a more secondary role next year with Paulinho as a super-sub (dont think he'd mind, really).
EDIT: Oh, and fuck Piqué. Send him to Juvenil B and have De Ligt line up with Umtiti, please.
To be fair now is the right time to sell Rakitic since he had a great season which i doubt he'll repeat and he is over 30 years old. IMHO now is the last chance to cash on him.
You don't sell a starter until you are sure you have a replacement for him. Raki is far from perfect but he's a proven player and still the best we currently have in his position. Buy Arthur and De Jong and see if one of them will establish himself as a starter (or at least show enough potential to do that in next season when they'll be fully adapted to the team) and then we can think about Rakitić's future. Selling him before that would be stupid imo.