For new developers getting started with electronics, it's often preferable to avoid soldering to take advantage of being able to change designs as needed. While the existing 0.1 Breakout Wirelings are excellent for the purpose of turning sensors or accessories into Wirelings, they require soldering, which can limit their marketable audience to only engineers who know soldering. And even if some of them would be willing to learn soldering, not everyone has the needed resources to solder components together.
To help new developers easily prototype and design, and to market to a wider audience, I suggest a 0.1" Breakout Wireling with either pre-soldered screw terminals or pre-soldered headers. Though it is an investment to pre-solder, the returns can be quite viable. The ease of buying and plugging in a pre-soldered system cannot be overstated, and having a pre-soldered option may prove the difference between selling a product or losing the sale.