Hi, Michael. To my mind, fiberglass is the best choice. I know that cellulose is treated for things like fire protection and varmin infestation, but fiberglass is so inherently resistant to these that it just seems much more natural. Some companies make insulation that comes wrapped in a covering that will still let humidity move through it. This will make the job very easy.
Installation is also a very easy do-it-yourself project. The material is readily available at home centers. Check your ceiling joist spacing to be sure and used the unfaced insulation. When you are around it, wear long clothing, gloves and a dust mask. It cuts very easily with a utility knife. Be sure that you do not block any eave vents and don't step thru the ceiling. Run some temporary lights into the attic to make working easy.
You might want to take some 3/4" plywood sheets up into the attic with you to help in moving around. These can also be cut to 2 feet wide at the home center for easier handling. Don't forget to insulate your ceiling hatch to the attic. This can easily be done with some foam and adhesive.
There are so many different configurations possible that it is difficult to cover every one. But the basic premise is to get the material loosely placed between the ceiling joists. Allowing it to pack down or pressing it down hurts it's efficiency. Go back and fluff it up if you have to. I know that this is a lot of instructions but it is easier to do than to tell you how to do it.