Is the terms "ludic" restricted to the rigid requirements that most game designers have for games? The
dictionary says "playful in an aimless way" and give "the ludic behavior of kittens" as an example. In that sense I'm totally not opposed to ludus myself. For me playfulness is a very important part of the appreciation of art. Kittens may be the ultimate art audience!
I always am a great fan of Roger Callois, from
Man, Play and Games (
Les jeux et les hommes).
He had four categories of games:
Agôn: Skill & Competition
Alea: Chance
Ilinx: Thrills
Mimicry: Pretence
And two extremes to define them:
Ludus: Strict play by rules
Paidia: Free play; unstructured and spontanious
Many games have elements from all. In his book he also describes the 'perversion' of categories such as alea with horoscopes (which are taken serious but are just a game of chance). I always think his book is brilliant because it derives sociology from play rather than play as as subset in sociology.
Most shooting games are agôn and ilinx with their competitive shooting and mindless explosions, many 'bored housewife' games such as peggle have large influences of alea.
Notgames would be low on agôn and high on mimicry, not being about skills and rather about pretence (seeing the situation as 'real').
These categories were a comfort when I found them studying gamedesign and being confronted with the singleton (somewhat childish) attitudes of most developers and their lack of language on this subject.