The best replacement for portage is apt.

The best alternatives to portage are rated as following:
★★★★★  apt
★★★  paludis
★★★  ports
★★★  timbuk2
★★  homer center
★★  chesterton
★★  northern cambria
★★  lake central
★★  merrillville
★★  crumpler
★★  pkgsrc
★  st rita
★  apt get
★  yum
  windber
  bishop mccort
  valparaiso

Your alternative for portage is not listed? Suggest!
Speaking about portage, one probably shouldn't forget about kayak.

Other search terms related to portage and their ratings are:
★★★★★ kayak
You have in mind a companion for portage and it is not yet here? Propose!



Google Trends

Scale is based on the average worldwide traffic of portage in all years. Click on graph for more.
portage
apt
paludis