I like 6x6 TLR cameras for their simplicity and light weight. But except for the Mamiya C cameras, you can forget about interchangeable lenses. For a really small light camera you can fit in the luggage or a pocket for trips, it can be hard to beat a folding camera, but let the buyer beware and again, forget about changing lenses. First maybe you need to decide if changeable lenses are what you need, and then pick a format. Or the reverse, pick a format and then whether you need multiple lenses. It is a matter of narrowing down the field. It can also help to make a list of features and functions you do NOT want. Don't go for bells and whistles, the general rule of thumb is get the more expensive simple camera rather than the cheaper do-everything camera. Generally, if you stick to known brands and models, it is hard to get a bad camera.