cfds might be on to something. Bryce's orthographic (aha! that's the word I would have understood had you used it in the beginning) views are intended mostly for the ease of placing objects in a scene and comparing size without having to deal with perspective. Even so, if you click on "Edit this Camera" in an orthogonal view, you'll see that the field of view is not set to 0 but rather to 10, so technically there is still some perspective being calculated.
But you can edit all the cameras if I remember correctly. Thus, as cfds suggested, you might try editing the director's camera or the perspective camera and experimenting with lowering the field of view to a very low amount. Bryce's default field of view is 60 degrees because it is assumed that you will be rendering wide angle shots of landscapes. However, I have both my director's camera and perspective camera set to 30 degrees because I often render interior shots or even portraits of human figures. A sixty degree field of view in those circumstances yields a distinct "fish-eye" view.

Regarding terrains...might I suggest making multiple terrains instead of trying to get intricate detail out of one terrain. I made a very complicated mountain shape in a fantasy image, but trying to paint the greyscale image using Bryce's terrain editor was futile. Instead, I made the mountain out of several mountains, so to speak. It worked beautifully. A lot can be done by using landscapes as components of an object. I've seen some people make building fronts and furniture out of Bryce landscapes.

Regarding the water...are you using a volumetric slab of water? There are two choices when you create water. One is a surface plane. The other is a volumetric slab that stretches out to infinity just like the plane. With the volumetric slab, you can assign changes in the material according to depth. Thus, you can have an object immersed in the water with part or all of it visible below the surface, and the deeper it goes, the more it disappears into the murk.

All of this is covered in the Bryce 5 manual, and probably Susan Kitchen's Bryce 4 software book that is still available through Amazon I think. But if you're a newer user of Bryce, how would you know as they stopped including actual manuals after Bryce 5? An excellent resource is the Bryce forum at Renderosity and the Bryce forum at DAZ 3D.

And me.