Djourou was excellent last year, and pretty much held our defence together on his own when Vermaelen was out, for the first 2/3 of the season. Has been pretty terrible since, and hard to imagine that we don't have a youngster with the potential to deliver better than what we've seen from Djourou for most of this year. Question with Djourou is where his real level is - is he a good player in poor form, or a poor player who had a good streak a year ago (or somewhere in between)?
I like Miquel, myself - I don't know how ready Arsene might be to give him games on a semi-regular basis, but if he chose to push him up a notch next season it wouldn't shock me any more than seeing him loaned out for the year.