Chelsea don't appear to have many major needs heading into the summer transfer window, though a replacement for Didier Drogba is near the top of that list. That is, unless Drogba decides not to retire, and continues with Chelsea for another season:
Drogba has been far more effective than anyone could have imagined this season, and gives the Blues two very different options of the bench late in matches or in replacement of Diego Costa. His power and hold up play are certainly useful in many instances, and they're a nice contrast to the skillset of Loic Remy.
The only real negative that I can see is that it means Patrick Bamford is unlikely to be with the first team next season, though he's rcently confirmed that he'd be fine with a Premier League loan. It sounds as if that might be the best opportunity for the striker to get acclimated to top flight English football, as if Drogba is looking to play and content in a backup role, I can't imagine he won't have a place at Chelsea under Jose Mourinho.