The current account wizard requires the user to provide technical details (server names) while not allowing to specify others (ports, security options) or to check whether the configuration works. Thunderbird's new Quick Account Setup (bug 422814 and its follow-ups) offers a "best guess" alternative without the above drawbacks.
You may want to follow bug 506290, which possibly changes UI and the workflow.
We shouldn't list each and every change to autoconfig here, but bug 549045 certainly stands out.
Any news after ~4 years?
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