The best replacement for steadicam is glidecam.

The best alternatives to steadicam are rated as following:
★★★★★  glidecam
★★★★  shoulder rig
★★★  dolly
★★  flycam
★★  shoulder mount
★★  gimbal
★  movi
★  handheld
★  rig
★  monopod
★  slider
★  fig rig
  steadicam
  gyro
  brushless gimbal

Your alternative for steadicam is not listed? Suggest!
Speaking about steadicam, one probably shouldn't forget about follow focus.

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



Google Trends

Scale is based on the average worldwide traffic of steadicam in all years. Click on graph for more.
steadicam
glidecam
shoulder rig