I mix a varient of D94a. I mix in everything but for DTOD. I have not had any issues with my soup when processing Foma, Shanghai GP3, ORWO UN54 or Kodak Vision 2/3 all as B&W reversal. I have not used my D94a (-DTOD) to process 7266 yet.
I have since moved on to Kodak D19. It is much easier to tear open a premix packet of powder when being lazy.
Also could I suggest that you give the sodium thiosulphate a miss. I do, and again I have done so since finding I cannot spot a difference between a 1st developer with sodium thiosulphate and a 1st developer without it. If you try without sodium thiosulphate and are happy with the results then run with it, if not then don't.
I also stay away from Permanganate Bleach because I have not had good experiences with it. Maybe I was doing something wrong... Dichromate Bleach has become my bleach of choice and proven to be reliable with all films I have used to date.