On this forum there is also a guy who built a .X exporter, try to consult him. Not sure what his name is; but a search should bring him up. Again, it is easy for someone to improve the exporter once they understand the API, just gotta encourage someone to do it.
As for your questions about Blender.
It all takes time, it took me months to learn Blender. I've read the Wiki about 3 times; reading once takes about 7 or 8 hours. Even then I was still a rookie (still am). In my opinion, it takes at least 2-4 weeks to get good enough in Blender to use it as your primary modelling tool, its interface has a long learning curve.
In combination with
decent video tutorials, the ones where you can actually hear what the person is talking about, it is a good way to learn.
Its ability to duplicate meshes at every vertex and its ability to shape, bend and deform characters, vehicles, sky scrapers or anything you put under a modifier makes it very powerful; and 90% of the modifiers work with the exporter. Mesh modifiers are a valueable asset to have; no need to manually duplicate building floors or bend road meshes.
I'm using Blender for what it is good for; animation, vertex manipulation, UV editing and things like that. Everything else I do in the engine; and DarkShader. The same way you would use Matrices for one thing, and 3D objects for another; it is down to what is good for what. I build my own level tools specific for my game mechanics; but there are editors that can be used in conjunction with Blender, such as 3D World Studio; but with these 'smaller' editors, the support is limited due to their unpopularity. I try to stick with the tools that have busy forums and plenty of people around to support your learning.
I've used Cinema4D, Max, 3D World Studio, AutoCad, Sketch Up; they all have their advantages, but Blender is free and powerful at the sametime. SketchUp is good for level develoment, but getting its files into .X is something I do not know how to do, I have not used it for a while.
If I was you I'd practice with Blender, and look into Shaders; I say this because with little money, the combination of Blender modelling and FX shader skills will allow you to make anything you want. You only need to learn once, and after that you feel stupid not bothering to learn this stuff earlier.
The key is to use Object Orientation; never do the same thing twice, just save what you did, and reuse it to derive a new model from an old one. Blender calls this
linking and appending from previous objects; once you grasp that aspect of the tool then it makes things so much easier. Another object orientated Blender concept is grouping, groups work like instancing in DBPRO; you make something, then you can just plot it around using instancing. You use Ctrl G to group a series of limbs in Blender, then your group is automatically added to the 'Add Object' menu, so you can plot them around nice and easily; you can even change the source object later to different original objects; EG, changing the leaves on a tree.
Finally, script plugins. These can be added to enhance Blender. There are scripts that can generate trees with one click of a button (I think that generator is for 2.4); because it has a large community, there are lots of plugins out there.
But, no general modellig tool or level editor can do better for a game than its own custom made in game level editor; you get to place objects there and then and you see how textures really look like, plus you can set your flags and game properties on the fly. Combine this with a model editor for creating 'base' models, then you are well set for productivity.
Primarily, you can model something in Blender, texture it, export it, load it in DBPRO and have the texture displayed on it; and any bone structure attached with one line of code; providing the material is in the same directory as the model. Anything beyond this requires some programmatic elbow grease; multitexturing, bump mapping, lighting effects, halo effects etc.
