UNderstand where you are coming from ,as I had a Canon 300D with kit lens, but found prices prohibitive to better the glass. In the end it worked out cheaper to sell & buy a s/h D70 with the excellent 18-70mm lens.
For your case if you stick with the kit lens, the best bang for bucks 2nd lens would be the Nikkor AF 50mm 1.8. Mine just arrived this morning from onestop-digital for £69 inc delivery :thumb: