Mmm... feeding tentacles
What I'd love to see is a 40k FPS with that level of graphics. It wouldn't be too feasible when you consider the usually high mortality rate found in the setting, but it would be kewl.
Play an inquisitor -> they just need to slap together a combobulation of the Starwars: Force Unleashed engine and Mass Effect together, change a few powers, reflavour a few that they keep [thats assuming you take the Psyker path], and alter the level up tree's [nick that concept from Too Human].
End result: An alternatable Third / First person shooter that allows you to have the option of ether mentally slinging around enemies with Psyker powers, or getting your terminator ontm
and whomping stuff into tiny bits with a big hammer, all while giving your retinue limited commands [having them chiefly rely on well programed AI to dictate actions] and allowing for both functional melee and firearms combat.
I should totally be in games design.