Pear was great back in the time, in the old days of PHP 3 with pear we had
ORMs, templates engines, debug tools, logging, caching and a lot of more
tools. The problem was if you wanted to include your new component in the
pear repository, that was pretty hard since it was a very closed and
elitist
I think that Doctrine is a good alternative, have several features.
http://docs.doctrine-project.org/projects/doctrine-orm/en/latest/index.html
Also have a version for Mongo as Backend
http://docs.doctrine-project.org/projects/doctrine-mongodb-odm/en/latest/
Another option is Propel, is more si