Bass guitar is different from regular guitar. For the most part, unless you're playing some jazz fusion stuff, it's one note at a time. Also, the bass style that I like is not trying to run the show but to provide a foundation for the other musicians to build on. A really good bass player can not only keep the beat but also move the song along rhythmically while permitting the vocals to remain pure and simple. Jim Croce and Gordon LIghtfoot are examples of what I consider this style of bass playing (and interestingly - same guy playing bass on a lot of the songs). But, bass can also create a riff that continues while keyboards and guitar are varying that theme all over the place. The Guess Who did that a lot, and Blood Sweat & Tears.
So, I'd say that playing bass is a whole different approach to making music than playing guitar. I find it easier, but it's where I come from. I've only ever played guitar in the way that you may have heard on my contributions to the Song Of The Month forum. Pretty much limited to country/folk style. But for bass, I've played orchestral music, show tunes, big band jazz, Dixieland jazz, blues, and Christian rock. And not only bass guitar, but also bass trombone, tuba, and upright bass. So I feel more comfortable being able to pick up a bass and make up a line that won't hurt the song and play with others than with guitar. But that's why I learned guitar in the first place. I mostly play alone in my basement office, and playing bass alone is kind of boring. The guys on the CD are going to do exactly the same thing every time and there is no spontenaity or connection. I much prefer when I'm in a band and the rhythm section locks in with one another and you've got rhythm guitar, percussion, traps, and bass all connected and creating an unassailable groove. That's heaven. But it's not something that happens alone. Whereas with guitar I can play alone (almost said play with myself) in my basement and still feel like I'm learning and improving and making music, or something that approaches it.