what should I upgrade next?

I had an old stereo system which consisted of:

NAD 302 integrated amplifier
NAD 502 CD-player
NAD 402 tuner
Linn Index speakers
Linn k-20 speaker cables
Sony DVD player

Few weeks ago I started upgrading my old system for HT. After some research I got the following:

Linn Trikan center speaker
Linn Unik surround speakers
Linn Afekt subwoofer
NAD T753 a/v receiver
Monster interconnect cables
(I will be using the old Linn Index in the front)

I am getting a new NAD T753 from my dealer, since the first one had the hiss problem. I hope the new one will be OK.
First, do you see something wrong with my choices (well I guess now it is too late since I made the purchase already)? What do you think is my weak point / or what should I upgrade next?
Your opinion will be very helpful, since I am a newbie.
Thanks!