The best replacement for peacekeeper is peacemaker.

The best alternatives to peacekeeper are rated as following:
★★★★★  peacemaker
★★★★  msmc
★★★  pdw
★★★  mp7
★★★  m27
★★★  an 94
★★  skorpion evo
★★  minuteman
★  type 25
★  mtar
★  pdw 57
  peacemakers
  an-94
  conscript

Your alternative for peacekeeper is not listed? Suggest!
Speaking about peacekeeper, one probably shouldn't forget about map pack.

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



Google Trends

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peacekeeper
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