I too remember having an overwhelming sense that Petofi was all-powerful, once he got the Hand back. This viewing, I noted how little his powers seemed to increase with the Hand, if at all. I also "remember" a present-day scenario in which the world was going to be destroyed, if Petofi got his Hand back (for the second time?)...
Tate's power was definitely given to Tate by Petofi. Petofi took Tate's power away for a few weeks, and only restored them in the final days of the 1897 storyline, for the purpose of creating Garth Blackwood to kill Aristede. So I wondered if Petofi had built a short time limit into this restoration, so that they went away shortly after this one purpose was accomplished. Petofi really had a lot of contempt for Tate at this point, who had been pestering and begging Petofi, with Petofi saying he'd never have his powers again.
It seemed as if they wanted to bring Petofi back, in the present, someday, but if he's dead, as it seems, that might have ended Tate's power. Or Tate's power could have been permanent as long as not removed by Petofi, but things seem otherwise.