If I did it again I would get drivers that are rated upto 80Vac/110vdc and use a 70Vac toroidal transformer.
Something like a 2*35vac secondary outputs wired in series for 70vac.
Doesn't matter wether you have Nema 17/ 23/ 34size motors etc, the drivers regulate output voltage to the motors themselves.

For the bb-e it needs 5v and 24v. Could use either voltage stepdowns from the toroidal or seperate switched psu's. Depending on how many relays you have will determine what amp rating they will ideally need to be.