I think it's vital to make cap diacritics flatter, and have them hug the base forms a bit tighter, or they stick up like luggage on a roof rack and collide with descenders. Much more importantly, that's what Victor Gaultney thinks, unless I misunderstood his Extended Latin workshop at TypeCon.
Also think you generally have to redraw the acute and grave if you're making them more horizontal. If the form looks like it's been rotated, someone wasn't taking enough care.
What was helpful for me was learning the term "spine." Once I started thinking of the middle as one of the main parts of the letter, rather than just where two curvy parts happen to meet, a switch flipped for me. Still find balancing S hard though, especially in italics.
Seriously, I think the only "trick" is to train your eye through the experience of drawing it (however you draw it) until you know when it looks right or not. There's no trick that will let you skip that step.
I don't understand the difficulty of this character? I just deconstruct the section mark and put the top and bottom of that together for both Ss. If I have dollar sign done, i just delete the bar and add a bit of weight to the diagonal.
I long ago realised that the trick to making an S — for me at least — is to completely ignore the middle section until the end, and to concentrate on a mental image of the top and bottom relative to each other. I usually create these as separate outlines, and move them about and adjust them until I am happy, and only then connect them. At that stage, if the top and bottom are solid, the middle section just sort of falls into place.
Here's my trick for drawing S: draw thousands of really crappy ones over the course of several years. Eventually you'll find that the S's that used to come out lousy—and you had no idea why—are coming out a lot better—and you still have no idea why.