Working methods with Mail

Question

My preferred working methods with email is to use everal secondary email addresses courtesy of my ISP. My old ISP and Thunderbird worked fine and did exactly what i wanted of them namely: multiple email addresses that can be accessed in a single application and those multiple email addresses to contain Sent, Inbox and Trash folders relevant to that email address (eg: 5 email addresses = 5 sets of folders).
Background
The above working method is worth my offort as it keeps the primary email address tucked away and scarcely used. Should a secondary email address become compromised all it is is a matter of ditching that email address and setting up a replacement for it. The above working method seems to solve spam or compromised address easily and in a timely manner.
For why?
Well I guess we've all received those group emails from someone with a less than acute sense of security. In other words there is a good chance your email address may be compromised because of the skills or lack of them in someone sending a message to you and 20 or 30 other senders. (I think the maximum number of email addresses I found in a body of a message covered some 100 - 150 people at various organisations).
So, I'd like to make an enhancement request for Mail to support multiple email addresses (note: not aliases) which act independently of each other.
Is it doable in Mail?

Answer 1

An example to elaborate
primary email address with ISP follows convention: [email protected] (never declare this and avoid using it)
secondary email address #1 for use with online banks and financial institutions:
[email protected]
secondary email address #2 for use with online purchases:
[email protected]
secondary email address #3 for use with people with unknown skills levels and/or doubtful security practices:
[email protected]
Now imagine that for some reason or other email address #3 has been compromised and starts to receive floods of viagra, ***** enlargement, sex online, spam, online bank spams and/or spoofs.
One could try to invoke all manner of filters (dodgy, well-dodgy) or simply manage the ISP accounts to ditch [email protected] and set up a replacement account of [email protected]
The second method seems (according to my own experience) work a treat.