For privacy reasons, you are supposed not to reuse addresses; that's why some people might not be in favour of your idea.
Adding contacts does not necessarily mean that you'll add a single address.
There are already some good approaches for that. For example
BIP47: Reusable Payment Codes. Samourai is already utilizing it calling it
PayNym.
This could be integrated into electrum allowing to add contacts without reusing addresses or harming the privacy.