Making radio friendly music is where the real money is at.
Having a fan base to live comfortable, or simply have a little extra spending money is comparing apples to oranges when it comes to staying underground or cross over to the mainstream. If you have the material for it & have a chance, take it. The mainstream and underground are the same in the sense that we as artist (if we make it) are loved for a limited time only, so might as well go for the jugular vein.
The radio / mainstream don't give a shit about you & at the end of it all neither does the underground. It's about family, not your loyalty to the streets / fan base. The moves we make are based on family and I will tell you this, my kids come before anything, so if the mainstream accepted me and wanted to take me in, you better believe I will milk that cash cow til it bleeds, and invest into something good to remain at that level when I drop out of sight from the music scene.
If the underground could make you rich and provide for your family by supporting, then I'd say different, but it's clear your not content on where your at right now in your career. That's why I say, go for it and only look back at the things worth looking back at. And disregard the rest!