Ummm... last I checked, breeders no longer exist. It has been replaced with the multi-machine processing of the depleted cells, which is currently the only known source of Plutonium in the mod.
Condensators, in general, are a huge trap. Basically, you throw a diamond chest full of stacks of lapis blocks (no, this is not an understatement) at a problem, and you can generate some pretty impressive numbers. However, you need to obtain 10k+ lapis per cycle somehow, which previously meant UUM. That is... no longer viable, and an energy-negative method (meaning it costs you more energy to produce lapis than you get out of your reactor).
If you want a hugely powerful reactor, look up CRCS. It swaps out cooling cells rather than condensators, cool them in towers, and replaces them. You can literally build a reactor so powerful that no known energy cable is capable of handling the output, and it will even cause HV Transformers to explode, due to producing over 8k EU/t