With the ex Haldanes store on King Street I would split the shop into 4 or 5 smaller units.Then stop the buses on that part of King Street and create a cafe/ bar in 1 unit with outdoor seating European style, and then create a space for street entertainment etc.
With Derwent Street at the bottom end build a news sports complex working with the Football club, Cricket, Tennis, Hockey etc, with first class swimming etc.
For the rest of Derwent Street build a Business Centre that offers a range of fully serviced office suites, heated workshops and practical industrial units as well as excellent fully accessible conference facilities.
Very much based on ideas from Coney Green Business Park in Clay Cross http://www.coney-green.co.uk/ .
If you think over the last 10 years Belper have lost many jobs from business's moving out of the Belper like Thorntons, Deb, Jaeger's, Fuch's etc, Belper needs help to create jobs for local people. We need to look at funding ie ask it to be a small Government Enterprise zone.
The North and East Mills need to be bought from the current owner and then set up as a charity trust, funded via the National Lottery.
These are just a few ideas, please put your comments here and then will pass this on to local councilors, MP etc.