I recommend switching to cold Sabouter, you will need any synergy you can get with Sabo. Sabo is one of the weaker and less reliable class combinations, so playing a Sabouter that is not in any way synergetic (Nightblade got no Lightning support) on Hardcore and trying FG/AoM content with or even Shattered Realm is suicidal. And even with cold Sabo you should expect quite a bit of problems in AoM/FG areas, Nemesis fights and Shattered Realm.
I would also recommend trying my cold Sabouter, here is the guide. It’s probably the only Sabouter spec that is both very tanky and reliable and very damaging at the same time. Please note, that you need that exact gear for build to work as it was intended and you also need to replicate my skill allocation and devotion map.