General :: Mutt Nested Mailboxes Navigation Possible?

I receive a lot of emails daily, and with the ever-growing amount of maildirs I'm in need to structure/optimize the browsing in mutt. My maildirs follow this naming scheme: .domain.category.sub_category

My goal is to break domain, category and sub_category into nested levels when browsing through the mailboxes. This is sort of achieved through the use of imap. But I stumble upon a few snags, so my questions are:

Is this nested mailboxes view possible by directly accessing ~/Mail and not using IMAP?
E.g. set folder="~/Mail" and set spoolfile="~/Mail/.INBOX"
When I start mutt I'm presented with all mailboxes available, which is what I want to get away from. I want to get directed directly into my default/main inbox like I do when accessing ~/Mail directly. How?

When hitting c (a defined macro, see configuration below) I again get presented with all the mailboxes available, and not the mailboxes at the current browsing level, e.g. mailboxes containing a specific category. To get this view I need to hit c+TAB. I've solved this by adding a <tab> to the c macro's. When finally getting mutt to present me mailboxes in nested levels they are only enumerated and not annotated with N, indicating new mail, or even better, total number of new mails in or under a folder. I know it's possible to define format on the different views, but is there one for this view? If so, which?

My mutt configuration:
set autoedit
set edit_headers
set reverse_name
set from='blapp'
set realname='Blapp'
set use_from .....

# Automatic viewing of html mail, but always prefer text/plain
set implicit_autoview
alternative_order text/plain text/html