Now not causing offence to guitarists, but don't listen to anyone when someone tells you that guitar takes more skill than bass.
If you are in a serious, proper band, where you alter how you play your song onstage each show and don't just play the same riffs allthe time, then bass is a very hard and time consuming instrument to learn.
Whereas guitarists play chords, and yes do riffs, you have to know exactly what notes go with that chord, and what notes will go with the next chord depending where it is etc.
Only poor bassists play root notes all the time, of course you can do root note basslines, they sound cool in the right circumstances, but ultimately being able to roll off an amazing run on bass takes an endless amount of skill.
Another point to consider is if you're planning to do session gig work, in which case you may be lucky to be given a chord sheet for gigs, but you'll often be told what key each song is in, and be told a vague outline of chords, but the guitarists alter the chords. In this case, you have to have the ear to pick out what they're playing and then think almost instantly what you have to play.
However, if you take time to learn all the theory side of bass, then it becomes a really enjoyable experience, you can alter the mood of an entire song by doing something on bass. I didn't have lessons for a while whilst playing bass, and I could play tabs of loads of stuff, and could make up simple stuff to guitar. However, I had a bass teacher who played in a rockabilly band, who does session work for other bands, he plays double bass as well so he really taught me about getting your ear in. Since that, my bass playing has improved drastically, and all I need to do in band practice is see what chords my guitarists play, sit back, lock in with the drums, and let the bass flow!
And yes, do a bass solo now and then, cos we all like to stand out in prog metal, don't we?
.
Peace.