This is not a complete answer, but it seems that passing the wrong attribute was all that was required, at least in the case of luminus, to get a list of attributes:
$ lein new luminus meh +meh Unrecognized options: +mhe Supported options are: +immutant, +site, +h2, +dailycred, +cljs, +sassc, +swagger, +auth, +http-kit, +cucumber, +aleph, +mongodb, +postgres, +mysql
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