1. What is the best tool for landscape architects when modelling terrain/topography? I have used various combinations of AutoCAD, Architecture, Civil 3D, Rhino, SketchUp and I still have not found what I am looking for. Which is an intuitive, dynamic, section and plan, push & pull tool. Any suggestions?
2. Do CAD users prefer working with colour-dependent CTB files/templates or have you converted to style-based STB ones?
I guess the question that jumps out at me is what kind of topography are you working with. Is it contour lines that are in an autocad type setting or is it something organic that you want to create form scratch? I use SketchUp for all of my modeling and have found it very good with contours out of CAD. There is also a good demonstration that was shown at SketchUp base camp last year by Daniel Tal (who is a member of Land8lounge) you can do a google search for "sketchup basecamp videos" and get a complete list, then look for Daniel's presentation, or try the link below...
With the direct 2D/3D environment in Vectorworks Landmark, you have several different ways of creating a terrain model, whether you enter X,Y,Z points you've gathered in the field, or if you import them from a Survey (ie CSV, TXT), or from contours generated on your own, or imported from other DWG/DXF, even GIS Shapefiles, you have a lot of flexibility in creating the terrain model. Once you have made it, you have the ability to show changes to the proposed site by modifiers, such as proposed contours or polygonal shapes with or without slopes. These changes can be reflected in plan, 3D and sections views, as well as quantified in Cut and Fill calculations and in slope analysis. The editing of source data for the terrain can be, as well as the shape and extent of the modifiers, so there is some aspect of push/pull already. Mapping textures and sending objects allow you to make the entire modeling aspect a real as you want to make it. It has been worth switching and learning the new tools, because they make my design/analysis process easier and faster.