I crocheted for more than 20 years before I learned to knit. I had tried several times, but I think my problem was that I had crocheted for a couple of years first, and knitting seemed so hard in comparison to how easy crochet felt by that point. And I was 10 or something at the time I was initially trying.

And as I got older, I just had more and more years of crochet experience, so the situation stayed the same.
Finally it clicked a couple of years ago, though, and now I primarily knit. I prefer the experience of knitting right now, although that could change in a few years. I think right now I'm still recovering from those 20 years of looking at patterns and having everything I want to make be knitting. (I'm not saying "knitting is better," just that Murphy's Law requires that if you can only do one craft, the other craft's patterns are going to look awesome.

)
I agree that continental is much more comfortable for me. Yarn just feels right in my left hand. In terms of the OP's questions, knitting was definitely harder at first (but, like I said, that was probably because I was comparing it to experienced crocheting), but is now at least comparable. (I feel like it's easier, but that may just be because I prefer doing it now.) Many (most?) people seem to prefer knit stitches to purl ones, but most people are willing to do both. (Some people tend to stick to garter stitch, which is all knit. I would probably suggest that in the beginning you not go too long just practicing knit stitches, though, because that can lead to the same sort of issue as I had with knitting vs. crochet. If you get really good at knit stitches, then starting over with purl stitches will really make purling seem tough in comparison. So I'd suggest practicing a bit with knit stitch, then when it just starts to feel like it's making sense, switch to purl, and then go back and forth in that way.) There's actually a decent chance that casting on will seem awkward longer than knit/purl stitches, because you're generally casting on just at the beginning of a piece, and then you get lots of knit/purl practice before you cast on again. You can, though, use the knitted cast-on, which works like the knit stitch. (I'm a big long-tail cast-on fan myself.)
Good luck!