I think part A contains the normal developing agents, and part B is the 'activator'. I think you want to focus on varying the part B for various results. More of it should accelerate your development if I understand it correctly.
I use 1+1+100 for my Tri-X, Foma 400, and some Agfa APX films at 16 minutes with reduced agitation (once every 3 minutes). For FP4+ I dilute more to 1+1+150 but keep the time constant. It works very well for me, and I have found no reason to experiment with it more.
To vary the relationship between part A and part B to other than 50/50 - I have no experience. I think you need enough of part A to make sure you don't exhaust the developer, and enough of part B to accelerate the development to your liking.
Someone with more profound knowledge will have to confirm this, however, as I am not generally interested in the scientific part of it.

- Thomas