Infact I thought about Romeu while writing that previous post. Only problem with these 19-21 year olds is that our midfield is far too crowded at the moment. We have Xavi, Iniesta, Thiago and Keita for 2 "creative" positions, and Busi and Masch for "destroyer" role. With Cesc probably coming, we have 7 players for 3 midfield positions. If something insane happens and Pep needs to find cover elsewhere, he'd probably try to use players like Afellay, Adriano, Messi or even Fontas as a temporary replacement. So young midfielders like Roberto, Romeu, Ilie, Espinosa or even JdS need to have insane luck if they hope to get any first team football in la liga next season as there are some 10 players above them in our pecking order.
Now for guys aged 16-18 things are completely different. As they are probably making their way to our first team in 3-5 years time. By then we dont have Keita and Xavi probably cant play more than 25-30 games in a season. Those younger guys will probably have lot less competition than these todays Barca B regulars.