Yes, that's why I'm considering 1st person by default.
And yes, the game resolution will change the desktop resolution if you go fullscreen (if desktop is not same res. as the game).
The game is quite pixel bound, this means that the higher your desktop resolution the heavier the game gets, that's why I force a resolution change to keep performance consistent and measurable.
However, the aspect ratio is a very good point. I can actually change the game's aspect ratio to match the desktops, and resize the engine's internal buffer to a smaller version of the desktop size, so once swapping buffers they will be stretched back to the original size, this will not change the desktop resolution and also keep the performance consistent. I will have a quality setting for that feature, so user can decide.
Thanks a lot for the feedback!