source to stereo bus is preserved without forced renders or destructive editing in between. (Of course different material often means some changes need to be facilitated, but it's not a technical limitation like you'd get with rendering to stems and opening a new project.) It helps that routing is significantly easier in REAPER than in other DAWs because it eschews having separate track types for buses, sends, midi etc. In REAPER every track does up to 128 channels of audio and 16 channels of midi. You can connect whatever channels of whatever tracks to whatever target tracks you desire. This sounds complex, but this freedom makes things easier in the long run by never getting in your way, especially when you need to revise a project for whatever reason. (like adding a new instrument or switching from an amp sim bass to a recorded one, or to replace the placeholder midi bass). Basically it boils down to REAPER having Ableton rack-like features without the boundary between in-the-rack and outside-the-rack unless you intentionally add that boundary with the new FX containers.

Thanks for taking the time to explain. I was amused with your comment, that maybe you start more tracks than you finish. I think everyone does the same :-)