Argonaut Knight. There's a phrase, "if it is not broke why fix it?" You must know a number of games that were popular then lost sales on the next version because it changed or lost features that made it great, then on the version after that tried to put back what should never have been removed. Developers bring their own bias into game design, which is often new for the sake of new. Being new can be brilliant, such as Far Cry 2 and Last of Us, to take two examples. But building on the success of a game means keeping what made players love it, and adding new to change the experience. Think of the F1 racing games and what makes them successful. They haven't introduced rocket engines, as an example, because fans aren't interested in that sort of new.
Certainly a lot of people willI agree with you that games need to avoid getting stuck but there are things that work and should stay there. Look at FIFA and it's only football! How long have people been playing football? So what makes people still want to buy football games with the same old pitch layout and ball?
This reply is not intended as an answer to all your points of view, just focussing on your point about re-using weapons. Would you want the main emphasis on fast hand to eye coordination in games? StarCraft is not about hand to eye coordination and there are world class players of StarCraft who never win an fps game. Blizzard gets it right becuase they have what players want and build on it instead of replacing it, and all game developers could learn from them.


