The best replacement for wgs84 is nad83.

The best alternatives to wgs84 are rated as following:
★★★★★  nad83
★★★  nad27
★★★  utm
★  grs80
★  gda94
★  itrf
  msl
  ecef
  wgs72
  mean sea level
  mercator
  nad83 datum

Your alternative for wgs84 is not listed? Suggest!
Speaking about wgs84, one probably shouldn't forget about utm.

Other search terms related to wgs84 and their ratings are:
★★★★★ utm
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wgs84
nad83
nad27