Suggestions for TreeTeX-plain

The following packages have something in common with the package TreeTeX-plain. The packages are ordered in decreasing similarity.

Package treedef: Macros to typeset trees in Plain TeX
Package plainmisc: Miscellaneous contributed macros for plain TeX
Package tree-dvips: Trees and other linguists’ macros
Package treesvr: Tree macros
Package qobitree: LaTeX macros for typesetting trees
Package syntrace: Labels for tracing in a syntax tree
Package eppstein-trees: Macros for producing trees
Package chomsky: Macros to typeset parsing trees
Package adtrees: Macros for drawing adpositional trees
Package drv: Derivation trees with METAPOST
Package dirtreex: Directory tree rendering for LaTeX with TikZ
Package dyntree: Construct Dynkin tree diagrams
Package familytree: Draw family trees
Package pstrees: Construct linguistics trees using a preprocessor
Package treetex-ltx209: Draw horizontally- or vertically-oriented trees
Package xytree: Tree macros using XY-Pic
Package xyling: Draw syntactic trees, etc., for linguistics literature, using xy-pic
Package ecltree: Trees using epic and eepic macros
Package rrgtrees: Linguistic tree diagrams for Role and Reference Grammar (RRG) with LaTeX
Package synttree: Typeset syntactic trees
Package williams: Miscellaneous macros by Peter Williams
Package baum: Trees, using PiCTeX
Package lingtrees: Linguistics trees preprocessor and macros
Package harvmac: Macros for scientific articles
Package resumemac: Plain TeX macros for resumés
Package letter1: Letter formatting macros
Package mlawriter: Write MLA style documents in Plain TeX
Package histyle: A HighStyle environment for TeX
Package automagic: Automatic counter numbering in Plain TeX
Package lextex: Typesetting legal documents using plain TeX
Package plain-widow: Three output routines that extend \plainoutput