1. Cooling with water inside reactor (realistic) is disabled
... Realistic ? IRL, it has to be done when ... this is your last chance. Look at Fukushima. By the way, it has been removed because it was OP.
2. Cooling with ice inside reactor (realistic) is disabled
That was just stupid (if you were creating Ice with Compressor + Pumps, and plz do not talk about EE --' ) since the numbers of compressor/pumps was high (it could have been more Solar Pannels ...), the number of cable + Pipes too (and if you got RP, you would just had used WaterBucket CASUC, not Ice one). And it's not realistic thinking the energy needed to produce ice in order to cool a nuclear reactor is probabbly bigger than energy produced by the Reactor.
3. Cooling with water outside reactor (realistic) is disabled
That was realistic (a bit), yes. But if you really want realism, you should think too about radioactivity --> second water circuits. And that was annoying to put all the Watersources around the reactor, thinking it happened very often to me to make it evaporate ( I was quite dangerous with my breeders, yes
). And external cooling was also boring for breeding (air cooling down by 0.1 :p )
4. Cooling with vents (unrealistic) is now mandatory (alternatives are even more unrealistic)
Just think it makes the heat go out by integrated water circuits. And in fact, it's easier than coolant cells to deal with, thinking coolant cells were cooling component AND heat absorbers. And if you really think, as I quote you after, that "realistic in this context is not just "like in reality" but also "like in Minecraft", you should have thought Minecraft do not care if vent or water-based coolants cells are cooling down, real life only does.
Moreover, I find it more realistic now, because IRL water cooldown by EVAPORATING (=disapearing for coolant cells). Okay, we could argue on this because water can transmit heat and not evaporate, but ... did you create the circuits to make the coolant cells transmitting heat to another circuit ? No, you just put coolant cell in your Nuclear Reactor, and it was supposed that heat was disapearing by itself.
5. Cooling with redstone and lapis (extremely unrealistic) are presented as a replacement for cooling with water. Insult to injury
It can seems you unrealistic but ... this is a HAYO-ish ununderstandable way of cooling down, still not discovered by our civilization, as we didn't discover yet Quantum Suit, Energy Storage device without any losses ...
6. Heating cells (even more unrealistic) added and is mandatory for breeding. What they do is great, but it would be better done with items that cool instead
Nope. I like what they actually do, and do not think it should be replaced by items cooling instead. There's no argue here it seems ...
And, "realistic" in this context is not just "like in reality", but also "like in Minecraft". Cooling with water is a part of vanilla Minecraft (water cools lava), and part of many mods (water is coolant in BC and RP). Heat=energy is a part of Minecraft (furnaces), even more so for IC (generators, thermal generators) and other mods (BC engines, RP thermopiles, etc). So, 1.3.2 reactors design contradicts established Minecraft traditions too. I'd go on (and on, and on), but again, it's a too big topic to discuss it here.
Nuclear rework has been done for:
Balancing game (avoiding easy-to-get CASUC but buffing IC²-Vanilla Nuclear Reactor)
Adding some new components to play with (because many players like having more component, just because Nuclear Reactor is like a game in the game. And we have to go deeper.