 The path tool can make profiles that can be extruded later. It takes some practice but lay-down the control points and correct them later. Be sure to change the # of segments between clicks to reduce faces when extruding. A small radius can have as few as 3 segments between clicks. Decide how many control points for your shape.
 | Lofting is making a custom poly and extruding and editting each layer as you go. Sometimes you move each point per level so try to keep it light.
Booleans are the most useful tools for relief , or real bumpy detail. Shapes need to be made to cut into the base object, then moved into position , and the trial and error begins. I always save a new scene version before a major boolean session.
After you make your cutting shapes, copy them before using and push aside just in case.
Booleans can also permanently join objects to lessen their polys or tighten the heirarchy.