Editing Salesforce Credentials

Right now it seems that when you set up a connection to Salesforce as a resource it will only use your email address to connect. Being able to set it up with a specific user credentials would be helpful for a few reasons 1) it means you can control that designated users permissions separately from your own within Salesforce and 2) it means that the data connection isn't tied solely to your individual account being valid (e.g. if it uses my credentials, I leave the company, and my license is deactivated that connection will fail, but if I could set it up with a designated separate generic login that that our company has set up, it would be resilient to staff turnover).