This took a frustratingly long time to make for the sole reason that the geometry is reeally uncooperative. I only tried two layouts but didn't really do much else. I also have a failed start height solve too, but I imagined it was better to finish this one because more people are going to get 1 start height than 8 latency. What ended up making it click was finding one layout and then realizing it was badass.

Start Height:
Everything has to start on a line, which means no tri-arms or hex-arms, and probably no min rate unless someone goes really crazy.
Piston arms and bi-arms are basically the only arms you should use. If your bi-arm is waiting long enough for it to become a single arm, you’re probably not doing the metric right.
Tracks are mostly useless except for waste chains—you would probably rather have an extra piston there or just remove the track and shift everything else closer.
I’m willing to bet the min rate solve with 1 start height is either 6 or 4.01.
Due to the natural nature of lines, it takes 3 turns for something to reach the other side—thus, it becomes valuable to minimize how much you do this.

Latency:
Min latency is 8, not using division. For Leaden Sea, a copper water and copper air go through three rejections, then bond to each other, then release their air, then output. For Star Tide, the copper air projects twice and bonds to an copper water and then outputs.

Some primary metrics feel more like restrictions than things to optimize. This is the case with both of these metrics. You are optimizing for the minimum cost while still having 8 latency, tiebreakers via area. You are optimizing for the minimum cycles while having everything start on a line. There are things like LexC, where if that is the first metric, you are optimizing for LexC, ties broken by whatever. If you're optimizing for cycles, then that's kind of whether minimum cycles is easy—if minimum cycles is easy to get, you're optimizing for the minimum whatever while still having min cycles, and if it's hard to get, you're optimizing for cycles, tiebreakers by whatever.