By all means, try the preferment overnite method to see what happens in your situation. Experimenting with varying amounts of SD at roomtemp or cold fermented, or a combintaion will give you different results, and none of us really gets the same results using similar methods because of our locations, ambient temps, dough handling methods, etc. Just a tiny bit of SD can turn a large amount of flour and water into an amazing dough...
If you consider that SD is already a long developing preferment as you are feeding it and getting it ready to incorporate into your dough, any amount might be viable in your recipe. While I don't exactly recommend using a high amount of SD, some of my best crusts used 40% SD. Getting enough SD to actually use that much in a recipe requires a couple of feedings over the course of a day or 2.
Once you inoculate any portion of dough with whatever amount of SD, you are on your way to basically making more SD. The hydration of equal amounts of the flour into the water for the poolish recipe does something to the flour that straight up mixing does not do. The flour molecules absorb the water and create a lightness. Some will come in here and say none of that is necessary, which may be true, but I definitely notice a difference in almost every weird tweak to dough formulas, or pushing the envelope that I try, and poolish methods have been very successful for me with both SD and yeast.
My next thought on using SD is to make a large enough feeding to get the bulk of the amount of dough needed for a recipe of 4 doughballs, and slowly adding in the salt and then enough flour until it feels more like a dough than a sopping wet 100% hydration mess. Maximum SD that would be ready to bake pretty much after balling and allowing a bench rest just long enough to regain extensibility. I'm doing that on my next dough making process just to see what happens.