help me make sonos better

you all know sonos does not serve the purity of detail/refinement market but it does do a fabulous job satisfying wife, kids, and even serious listener's who are working on "honey do" lists...

but there must be a way to make it better. read about the cullen mods and external dacs and am ready to dive into the water but for the life of me can't find the ultimate pool. can/will someone lead me to the right place? what and how much $ would be nice to know as well. many thanks....