The Mamiya Press is very heavy, probably around 2kg so you wont want to look at that either
The Mamiya Universal/Super Press cameras are not light, but heavy is relevant to each individual. When I first acquired my Super Press, in my 30s, I routinely carried it and a 35mm system on trips. Now I am older and have more lenses. I bought a 65mm lens, extension rings, GG back and cut film holders. Not so easy to carry. Now I have the 50mm, 150mm, and the 250mm f/5 lenses; also more backs. That fits in a smaller aluminum case. I would not want to carry that now.
But a wide strap for the camera (with 100mm normal) makes it easier to carry. With the 50mm and one of the telephotos, depending on the shooting I expect to do, and an extra back, all in a backpack, it isn't so bad. I would not want to carry it all day I don't think, as I developed a back problem a year and a half ago (not related to the Press
😀) and that wouldn't be fun. But the photos I could get would be fun.
The Press is a system camera. It is not an SLR so loses some weight there. You might want to pick up one and try it. If you like it, you can buy other lenses/accessories as you want and can afford. If you don't like it, the prices seem to have been holding fairly steady so you should be able to sell it with little or no loss.
It is cheaper than the Mamiya 7 system, and possibly the 6 system as well. It is also older, so you need to shop carefully. I don't know about any of the other cameras mentioned.