The best replacement for tikz is pstricks.

The best alternatives to tikz are rated as following:
★★★★★  pstricks
★★★★★  metapost
★★★  asymptote
★★★  inkscape
★★  graphviz
★  xypic

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

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



Google Trends

Scale is based on the average worldwide traffic of tikz in all years. Click on graph for more.
tikz
pstricks
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