Well, I'm slower than Lotsofsloths(average and single times in my signature) but I use opposite color solving, extended cross/block-building, empty slots, and LL edge control/orientation control with my last pair(which gives me a decent amount of OLL skips). Of course, in F2L your main problem might be look ahead as with most other cubers. When I really look ahead(anticipating every single step and how to solve it) I can get 16 seconds and below easily but when I am just going regular, everything above 16 is what I get. It is really hard to look ahead so I think that is the one 'trick' you should really try to master.
Also, it should not take you more than 8 moves for each corner edge pair. If it does take you more, either find a different way to do it or learn the algorithm.
I do suggest that you learn as many F2L tricks as you can(although multislotting is a bit much). Don't assume though that it will make you instantly faster. With various tricks you will find that it will actaully be even harder to solve fast until you can look ahead an do each case efficiently.
Remember: learning more is always good but looking ahead will help you alot in the long run.