I hear you and have done what you suggest above on dozens of builds. I have a very large basement bike shop separated into two different areas and have done well over 100 conversions to SS/fixed as well as many many more rebuilds of all different spices. At this point I can get very picky and creative on/about what I build as my bins are full and I have the means in both shop and time. I have taken old MTN bikes that were thrown to the curb and converted them into fixed commuters/grocery bikes/tame single track lovers. All for no money, only time and a bit of thought from the melon. I love bikes.