Wow, this place is amazing, thank you!
OK, so let me just say that drawing itself is a great hobby! Strange as it may seem, as you get better at drawing, the software itself starts to lead you. Whenever I start something it takes me forever to "see" what I am going to create. Finally, once the pieces fit together, literally, in my mind, I start chopping away at the block of marble, as it were.
Really, you will get lost in the drawing, once you've worked through the learning curve. So, as I've mentioned before, spend a little time really getting to know what you want to create before making a decision about what software you want to use. It's a little like buying a kit. As I've said many times when selling kits, it's not the money; it's the subject matter. If you are excited about the HMS Victory, even a beginner will make that work. If you couldn't care less about a rowboat, no matter how easy it is to build, you won't finish it.
It's the same with the software. The excitement, and the missing pieces, seem to be in organic fixtures.