I came back after almost 5 years and did the new war about 2 weeks ago. I did it with a rank 0 no mods nechramech and had no problems. You only use the necramech for like 10 minutes. The New War was my first time using a rail jack. I had no intristics and no mods and still managed to do it. I would recommend getting at least enough intristics for speed, a crew member, and some basic mods to make the railjack section less painful and slow though.