There are lots of other specific recommendations that could be made. The simplest, to start, is just to focus on the development of your scene for as long as possible, and assume that a lack of quality is likely down to needing more work on scene details, lighting, clouds, atmosphere, etc. rather than lack of render quality. Leave render settings at the default for as long as you can, especially while working; in fact you may even want to reduce detail and/or AA during scene development, for quicker feedback. The rendering "degrades" in quality fairly gracefully and accurately in most respects, so if you see something you like in low detail, it will probably look even better in high detail; trust that and keep tweaking, maybe do a crop render at higher quality to see, but stick to adjusting detail and AA at first, and keep below detail 0.8 and AA 8 until final render.
Those are my simple recommendations to start with. If you have more specific questions or quality-related problems let us know and we can probably give more specific advice.
- Oshyan