I'm new to 3d printing and have a CR-10 coming in a week. I have 3 noob questions.

1. What exactly is Cura, and is it necessary if you have software that generates .stl files? I have and am proficient in Sketchup and Rhino3d. Both export to stl.

2. Based on it's properties, I'm hoping to print ABS. It seems bed temperature control is critical for ABS and many people recommend enclosing the unit and/or insulating under the heat bed. (I watched a few of the videos on this.) I wondered if anyone tried using computer thermal paste between the heat bed and the glass plate? It occurred to me it might facilitate faster heat transfer and reduce heat up times.

3. I intend to build bicycle parts and chose ABS for the strength and better outdoor properties. It there another filament that might be better for my purposes that is compatible with the CR-10?