A lot of people think he's never fulfilled his promise as a player, and he should've been better than he is. Either way, if they think he would've fulfilled it staying at Everton they're deluded, IMHO. He may not really have done it in an England side, but who has in recent memory? At the end of his career he will have won every domestic medal and the Champions League.
The reason I wouldn't want him back is I don't think it will be fun to watch a half-fit Rooney huff and puff his way around the centre circle. With his love of ale, and the cigarettes, I fear the 30s are not going to be kind to his physical fitness. Occasionally players retire before their time (Cantona was one) but in Rooney's case he won't need to play on to his mid-30s, and unless Coleen fancies one last payday living it up in the US, I hope he does retire at the end of his current contract rather than give the romantics their wish and come "home".