The 2017 Typed Racket POPL Paper, "Type Systems as Macros" says that there are several alternative Typed Rackets: for example, typed rackets that do and do not have subtyping. Each sub-language is represented by a color in Table 1 on Page 8:
Where can I find and experiment with these language variants?
I am not seeing them in The Typed Racket Guide nor in the repo.