Hi, I am new to MWO, but it seems to me that single heat sink builds are completely useless, or can only be used for unbalanced meme-builds. It is caused by the TYRANNY of the gigantic bonus double heat sinks get within the engine. Sure single heat sinks add 1,3 of heating per ton while a double 1,5, while using 3 slots, but inside the engine the double heat sink gives 2,0 of heating per heat sink, which is almost unbeatable without a ridiculous amount of external single heat sinks. It doesn't get better with larger mechs, because those have bigger engines with additional heat sink slots where more double heat sinks can be placed. So at the end, only if you are investing an unreasonable part of your weight into heat sinking that you need to rather conserve slots than weight, you actually get ahead with heat sinking capacity compared to the doubles. I think they should get rid of the buff for doubles within the engine for balance. It is enough that they are buffed by the fact that they take up the same space and they would still be the choice on mechs where you don't need a lot of heat sinking, but at least the single ones could now compete on the ones where you need to install quite a lot of them.
You are correct that single heat sinks are useful on only a handful of meme builds and not much else. And I don't see that ever changing. I really don't think it's a problem. The only thing I think they might do is allow mixing of single/double in a single mech but that is probably a major change to how mech design works under the hood so don't get your hopes up.
"I really don't think it's a problem" - yeah, they have a dead pseudo-option for configuring mechs. They can fix that by nerfing the bonus that doubles get within the engine, it is definitely doable.
The big alpha's are fun. But without sustained cooling, you are generally going to have problems. Especially for slow mechs that could boat single heat sinks. _