Hi I also live in Basingstoke and as far as I am aware there are still a lot of cabinets not yet done. The first phase did around 77 and a further 20 or so were done last year but the exchange has 170 cabinets overall.
This map shows all the known cabinet locations and this web page contains useful info. They are a bit out of date as the camapigners have got their connections so have less motivation to keep the campaign going. Suprisingly Basingstoke and Deane Council applied a lot of pressure but they seem to think the job is done you might find giving your local councillor grief might help.
What is missing from the reasons you quote why your area has not been done is economics. In areas with new build cabinets are not yet fully used so economically may not meet the business case I know that many new build areas round here are still waiting. It may also be that BT are also trying to get developers to foot part of the bill so installing the service anyway does damage that idea.
