I suppose that by "carriers at war", you mean the recent version, released by Matrix.
This is really a niche market game. The principle of the game is not unlike a tabletop naval wargame ( I mean, with small models that you move, dices and a thick booklet of rules ). The game takes care for the nasty bits ( no need to have played and enjoyed armada to play this, fortunately ). I played the original extensively ( I still have it, installed under Dosbox ), but found that the 2nd was both awfully expensive and more limited in scope.
Sengoku is the typical paradox game, It's not that different from EU Rome , except that the game is set in the XVIth century Japan. The game mechanic fits this place and time even better. But it has quite a steep learning curve. If you have ever played and liked one of the Europa Universalis Games, this is a sensible choice