As noted, the long form is always possible, though less compact, since it usually requires a repetition. I suspect the short form is mainly for hideous examples and showing off -- and maybe some forms of poetry or oratory (which probably come under showing off).
"move into" is probably 'tawa insa' since the moving isn't inside.
tp, as a conlang, has built in its schematics something about being more like a natural language than a logical code, so a few oddities are to be expected. I'm not sure 'ni pi mi' really is that odd, and certainly wasn't back when 'pi' always meant possession.
Of course, as a transitive verb, 'lon kasi' means "put in a tree" as much as "created herbally" (more so, I would think, since the latter does not make a lot of sense).