But is that a military rank, or a political one? Himmler was no soldier, by any stretch of the imagination.
As long as we are talking about the Waffen-SS instead of the regular SS (more or less a government institution), Reichsführer is a military rank.
But according to that very nice German rank table you showed us, Goring was Himmler's equal in rank, not so?
Equivalent in rank doesn't mean equivalent in favour with Hitler. Also Ranks in the military have seniority so a more Junior ReichsMarshall/ Reichsfuerer is not the same. I know we are talking different arms but the gist is there. When the Squadron Sergeant Major is away the Senior Staff Sergeant is in charge, usually the SQMS who will probably the longest serving, /s technically they are the same rank but one is more senior.
After working with NATO all are quite different. The Table is wrong as Tech Sgt is a USAF rank and not an us army rank, but there is and equivalent in the us army.