Nuclear Reactors are great and very useful, but the loss of one can be bothersome since it can happen at anytime, even when ideally stored. I was thinking that having an optional cooling method like adding a bucket of coolant (water mixed with redstone dust or maybe copper dust) or putting a bucket of water in an extractor to get some Heavy Water used in cooling nuclear reactors and regulation of the reaction. To balance the heavy water, each water bucket extracted would yield 1 piece of Coolant, which you combine 8 pieces to make a coolant rod that you can put the the upper slot when the reactor is running to make sure it doesn't explode. Each coolant rod lasts maybe 32 uranium ingots.
Alternately make a cooling machine you can connect to the Nuclear Reactor that uses coolant to cool the reactor. Uses same coolant as above, but at a rate of 1 coolant rod for 64 uranium ingots, and can be used to cool up to 6 reactors at the cost of higher coolant use.
Not sure how much is really needed or feasible, but thats my suggestion.
