Should I trade my lenses for one better one?

[reygjabla]

Thank you for your suggestions, quite a few things to look into. The 24mm is probably might current favourite so it's unlikely I would get rid of it.

17-55 would be a good shout, but £700 is a lot of money, although it doesn't really loose value but you obviously still need to fork out for it in the first instance.

I guess the 2 18-55's, and 28-135 won't be worth more than £200ish?

You can get a qoute from MPB for those lenses or use it to partly swap for a better lense. If there's any chance that you might upgrade to a FF body in the not too distant future, then get an EF lense. They can be used in either Crop or FF body anyway.