@amlan image quality of last 4 years DSLR are almost similar from D300, D90, D3100, D5000, D5100, D7000 and D7100 ...all are almost same...you have to pixel peep to find changes...they say that DR improved and ISO improved...but you can not find much difference
when I bough my DSLR kit and 55-200 both I bough from local store
I bought 50mm 1.8 , 55mm 2.8 micro and tamron 17-50 2.8 from jjmehta forum
bough flash from ebay.com
tripod local store
triggers from a faceless store in kerela which all photography community knows...and he gives best deal
bag from flipkart
so no definite pattern
the only two things in my list now ...a D7000 or a D7100 and Sigma 150-500 or Nikon 300mm f4 AFS + 1.4x TC
I am waiting for my next visit to india in december to get DSLR upgrade 1st.