You know what I don't like? I don't like increases that are too obvious. For instance, when you increase a stitch in crochet and the stitch has an obviously larger hole because there are two stitches in it. What I have come up with to correct this is to make one of the stitches in the back loop and the other through both loops as usual. If the increase is at the edge, make sure the stitch that goes through both loops is also at the edge. If you have a troublesome horizontal loop, then make your single loop increase stitch through the front loop on right side facing rows and through the back loop when the wrong side is facing you. I haven't seen this anywhere before, someone else could easily have suggested it, but I do want to pass the word along.
Increases in knitting are interesting because there are different ways to do them. Yarn overs leave a hole, which is great for lacy things. Knitting in the front and back loop of the same stitch leaves a little horizontal bar which you may or may not like. Picking up a loop through the horizontal bar between two stitches is the increase I usually use because it is hard to detect and it is easy to do. Picking up a stitch in the loop that lies in the row below the stitch where you want the increase is also interesting to try.
So go forth and multiply those stitches!