We're Only in it for the Money is that sweet spot between avant garde and rock/pop, and a good sumnation of Zappa/Mothers up to that point. Other albums from this Mothers era can be challenging to sit all the way through. I'd then jump to the "Roxy" era Mothers (one of the last and most talented lineups). Look for Roxy and Elsewhere and One Size Fits All. I'm still trying to get into The Grand Wazoo and Waka/Jawalka - some interesting points, but too noodly to me. Latter Zappa is fine, but I just can't with the cringey oversexualization in his lyrics.