Poltergeist, out of interest is there a reason that you are using outdoor speakers in your system? As others have said your amp is the best thing you have got by far, and it would make sense to start gradually rebuilding around it as funds allow.
But first it would make a lot of sense to either find a dealer that has that amp and demo some different front ends and speakers with it, or take it with you to a non-Naim dealer and again try some different combos - that way you will know whether it really is the amp you want to change or (more likely) the speakers and CD player.
Also, you don't give your budget, but it is always worthwhile keeping an eye on ex-dem stock at the dealers (particularly for CD players and speakers whose models change far more frequently than amps so there is often a last years model going cheap).