There are cradles you can buy that will increase your coverage and charge your phone, that can then be paried up to any bluetooth car kit. You will struggle to find a kit like you are speaking about without spending $500 on a Bury / THB kit.

I presume you need NextG for the coverage? If so there are cradles available for the Nokia 6120, E51 and N95 that do all of the above.

As for the leaving the light on, im sure there would be a setting you could change for backlight timeout whist in a particular profile.

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Tuned Ugly Betty!