eQmail or s/qmail

Since the previous century we are running several mailservers on qmail,
serving around 6000 domains with about 4000 mailboxes.

All systems are based on the original Qmail-1.03, with the standard
patches, and all run on a single UID, based on Paul Greggs howto:
https://pgregg.com/projects/qmail/singleuid/

Spamfiltering is done in front of Qmail, with assp. So no hookups needed
for this. (assp listens to port 25, qmail to port 125)

Ezmlm is also in use.


Because of the several patches the last years (some have TLS, other
IPv6, some both, some none of these), we want to make a new fresh start
with compiling qmail on our servers.
Our systems are mixed-OS's, most run on Slackware, some of them on
CentOS, so I want to compile the things myself.


Which package should we follow?
eQmail, s/qmail, or are there others?

Any tips are welcome.

Best regards,
Pascal Nobus