Well, here's what I think: All kinds of things are enjoyable that don't necessarily lead to orgasm. The switching around of thrusting is fine because different things can feel good, and unless you are very familiar with this partner, you need to find what particular speed and angle and depth etc. the other person enjoys. But I believe most people would say that when you can sense your partner's orgasm is approaching, stick with whatever movement was getting them there. Do not deviate from the actions that are working until your partner is satisfied. That's my opinion on intercourse.

I can't speak to the oral sex thing because it's a complete mystery to me how any woman could ever orgasm from that.