Keep practicing your arpeggios! Learning to use them will be much easier if they are totally second nature and easily under your fingers. Eventually you'll start to learn songs you like, and then you'll realize when arpeggios were used in cool bass lines, and everything will start to come together. In fact, if you already know some bass lines you like, try to analyze them in terms of chord tones and scale tones. Also realize that often in practical use the entire chord arpeggio may not be used, but just two notes of an arpeggio, and that quick chord cadences can often be outlined by partial arpeggios. For example, "Fool In The Rain" by Led Zepplin, the cool bass part emphasizes the 6 feel in verses, I don't know, maybe 3 and 5? - verses before the calypso breakdown - use a very fast partial arpeggio movement in the bass line. The outro, on the other hand, uses scale fragments, so although many will say "chord tones more important than scale tones" take that with a grain of salt in my opinion. That said starting with arpeggios and chord tones is the way to go, fill in the more tension-creating notes from scale tone knowledge later on in your quest.