Don't Fresnel the camera unless they actually sell a Fresnel lens for that camera. I don't know about your specific camera, but putting a Fresnel lens on some cameras ends up shifting the plane of focus out of the plane the film resides in. If a Fresnel is offered by the company for your camera, it is probably okay.
I have a screen that isn't exactly the brightest in my graflex, but I've usually just focused it at wide open then stopped down for the exposure. If the ground glass is fairly unevenly illuminated or too dark, I would suggest a boss screen. I heard some people had issues with the beat tie screens, and the bosscreen is usually pretty recommended, even though it dislikes temp extremes.
Just my $.02