I'd like to suggest fixing condensators to work in fluid reactors, and find a way for MOX fluid reactors to output more heat. I have suggestions after my reasoning on why they need to be fixed, which is mainly "complexity should bring reward".
Fluid reactors are limited by the amount of heat they can transfer, due to the space and component limitations inherent in the fluid reactor itself. Practically, this is about 1370 HU/t. That translates to 1027 EU/t.
Fluid reactors are completely dependent on heat output to generate power. EU reactors are not.
My assumption for UC2 is "complexity brings reward".
MOX EU reactors work differently than fluid MOX reactors; the result being they are not dependant on heat and don't dramatically increase heat output the way fluid MOX does. This allows for EU MOX reactors that can put out more power than a fluid reactor, and still be simpler. This is the first issue I'd like to suggest fixing.
Condensators remove massive amounts of heat from an EU reactor, allowing for incredibly efficient models at the cost of component loss or repair. Unfortunately, they do nothing in a fluid reactor. This means a condensator EU reactor can be 3x the power of a fluid reactor at much less complexity. This is the second issue I'd like to suggest fixing.
1. Fix condensators. I suggest changing the condensator code to the following:
1. Pull heat and add to condensator, remember value
2. Vent heat
3. Add heat value a second time
This does the same thing as the current code, which I expect is "pull heat but don't vent", while also making the component work in a fluid reactor. Just adding 2x heat will break the condensator 1 tick prematurely but could be an alternative.
2. Fix MOX fluid reactors. This is much harder.
My suggestions are any of these:
1. Add code to all vents to allow additional venting when heat is above 50%, to keep up with the additional MOX heat
2. Add an "extra cooling" block that works when the reactor is over 50% heat
3. Have MOX add 100% to vented heat, not to produced heat.
Each of these would allow the MOX effect to increase the heat produced by the fluid reactor, and I think that is the point.