Im currently playing a self found burning discharge build on rampage. Im
Level 82 and running 68-69 maps very easily. I often kill most mobs with the initial hit before burn even sets in. My strategy revolves around using spell echo on enduring cry to build the charges and using es gear with EB and arctic armor to deal with reflect and not need armor. I also use flame surge to nuke bosses while keeping them ignited with discharge for the bonus damage.