Check my power supply calculations?

[Voicecoil]

The one advantage of slightly over-sizing the transformer is that it will tend to have better regulation (less difference between on-load and off load voltages) - this means there's less likelyhood of the off-load voltage rising to the point where it's getting close to the maximum rating of the driver modules.

There's one downside with a big toroid. When it's being energised it sucks a lot of power. You could see the lights dimming for a fraction of a second and even your circuit breaker tripping. Large transformers usually have a soft start circuit.

BTW, you can buy off-the-shelf soft start relays/modules if you hunt around, or you can make your own - they're pretty simple, just has a resistor of 10...20 ohms or so in series with the transformer primary to limit switch on current which is bypassed by a relay after a short time when the core remanence has been sorted out and the capacitors are all pretty well charged. Otherwise make sure your mains switch has a decent inrush current rating

And IMHO it's worth putting an LED with suitable series resistor to indicate when those caps are carrying voltage, 20,000uF charged to 45V will make quite a crack if your screwdriver gets too close to the terminals!