I'm a fan of cellulose. As long as you do the proper prep-work (put
vent baffles in for eave-vents, pre-mark your desired insulation depth
on the trusses/rafters, use plenty of plastic sheeting to isolate the
rest of the house from your work to keep the dust out, etc.), it's not
difficult for a DIY'er with a helper. The helper has to be JUST smart
enough to be trusted to keep their fingers out of the blower (a tiny
bit smarter would help, but isn't 100% necessary).