Yeah, some kind of ancient weapons FPS where your mouse actually controls the weapon in 3-D space. You could have things like jousting on horseback, throwing spears, using large pikes, or that ball and chain thing from Castlevania (dating myself a bit with that one

). A plethora of swords of course, or you could even have bows and arrows of different types. However, instead of the simple point and click button mashing, your mouse would actually control the weapon in a free-aim 3-D space type of fashion - so there wouldnt be a small set of animations, but a rather large set. You could swing your mouse in an upward half-moon motion and you would see the sword make that exact move on screen. Much like the pilot of an Apache helicopter, wherever his head moves the chaingun underneath the copter moves the same - it would be like that but with your mouse... the actual movements you make with the mouse would translate to your weapon on the screen.
For defense you would have to hold the right click while making mouse movements, or something like that. This way, you could strike at small specific areas on an opponent, and just generally have way more control over your fighting. There could be stamina qualifiers and such so that if you made too many big, wild and heavy strikes with your sword, while wearing armor (or not), your guy becomes tired and is barely able to defend himself... in this way there are many things to think about when in battle so the depth of play and skill needed would depend on the player. It could even be set in many different types of locales or periods in time... like feudal Japan, or the wild west with Indians, or Midevil Europe... whatever. Yeah, we need a badass melee FPS with a deep combat system. There's a genre that hasnt been fully recognized. What we DONT need is another modern combat game *YAAAAWWN*