If you're getting at what I think you're getting at (namely that using class/interface inheritance via C# code rather than ability inheritance via my library would be more efficent), I don't disagree, but that rather defeats the purpose of the library, since if I hardcoded more relationships, that would make the library less flexible.
I have hardcoded a few relationships, of course - with nothing hardcoded, there would be no code at all and it would be completely useless! For instance, inherent abilities are ALWAYS inherited from an entity's archetype, up the hierarchy of archetypes until a circular relationship is found or there are no more archetypes. Of course, if you don't want that to happen, you just don't set an archetype.
I guess what I'm basically doing is implementing a sort of pseudo-object-oriented framework in an object-oriented language. It seems redundant at first glance, but I'm not just designing for the end user (i.e. a programmer using my library), I'm designing for the end user's end user (i.e. someone with programing knowledge who wants to script/modify something written with my library).
Keep in mind also that the whole ability thing isn't everything - since this is for strategy games in particular, I also plan to have coordinate systems such as hexes and Cartesian planes, and a knowledge system whereby a user of the library can create "reports" on entities, which basically say what the location of an entity was at a point in time and what its abilities were.
All that a player will know about, incidentally, is the reports that he or she has received - only the game host will have the actual entities, so as to prevent cheating and reduce bandwidth usage! Actually, I suppose when I implement the player class, to avoid wasting bandwidth retransmitting old reports, I can just have the reports cached locally on the player's machine... that was one of the flaws of the "Cosmic Crises" game I was working on at one point (not to mention of SE5 though only with log messages and combat replays
) - old reports were retransmitted every turn, bloating the turn files! But then that might not be so great as you'd have to keep all your old turn files around to actually access the reports... hmmm...
Of course, if you're not writing a strategy game, you can ignore the reports, and if you're not even writing any sort of simulation of a physical space, you can leave out the locations, etc.
Writing a utility library is really a balance between 3 things: the ease of writing the library (e.g. how long does it take to write?), the comprehensiveness of the library (e.g. does it do feature X out of the box?), and the flexibility of the library (e.g. is it even possible to do feature X and still use the library?). Increase one and you must decrease one or both of the others
