You've nailed pretty much everything with this demo, including the controller support - really big kudos for that!
The main mission is short and sweet, didn't have any trouble. The VR missions are a FANTASTIC addition, though the third room camera change is a bit rough.
I'm not sure about the tank controls since I ditched them in favour of a more comfortable stick movement. It worked great. Combat is slow, but pretty engaging, found myself relying on the dodge a lot.
Graphics are probably my favourite part of the game, they don't feel "inspired", they feel like "they are" the PS1 graphics.
I don't have enough nice things to say bout this game. But I played with a controller, so maybe its different when you're playing on a keyboard.