Usability

Is there a shortcut for compiling and loading source files?

Yes. With most backend Prolog compilers, you can use {File} as a shortcut for logtalk_load(File). For compiling and loading multiple files simply use {File1, File2, ...}. See the documentation of the logtalk_load/1 predicate for details.

Is there an equivalent directive to the ensure_loaded/1 Prolog directive?

You can use the goal logtalk_load(File, [reload(skip)]) to ensure that File it is only loaded once. See the documentation of the logtalk_load/2 predicate for details.

Are there shortcuts for the make functionality?

Yes. With most backend Prolog compilers, you can use {*} as a shortcut for logtalk_make(all) to reload all files modified since last compiled and loaded, {!} as a shortcut for logtalk_make(clean) to delete all intermediate Prolog files generated by the compilation of Logtalk source files, {?} as a shortcut for logtalk_make(missing) to list missing entities and predicates, and {@} as a shortcut for logtalk_make(circular) to list circular references. See the documentation of the logtalk_make/1 predicate for details.