List versus tuples is easy though; generally your data has a fixed number of elements (tuple) or it doesn’t (list).
There isn’t a sound-byte on this page, but the elixir-lang tutorial does give good guidance on Keywords versus Maps. Keyword lists are ordered, and can have duplicates, but have linear performance. Maps are not ordered, cannot have duplicates and perform well with large numbers of elements. Keyword lists are used commonly for optional arguments and have a constructor syntax sugar for this reason, but one flaw in this purpose is that pattern matching the keys is impractical as you must match them in the correct order. An interesting workaround for this is employed by the Phoenix framework; when you call render in a controller the last argument is a keyword list so you can easily pass assigns. When you define render in a view, the keyword list is converted to a map so you can pattern match the keys.
Structs vs. maps I think is a little more nuanced. Structs have some requirements: fields are known up front, keys can be atoms, sensible defaults exist. But even if all those hold true you may still use a map if the scope / lifetime of the structure is very small, such as a map that is only passed between 2-3 functions. When the scope or lifetime of a structure is larger (used in multiple modules) it may make more sense to define a struct.
