Well, I just completed my first try at stippling and I have to say, It looks ok. The length of the stitches really depends on how fast you're going. The faster you travel the smaller the stitches I have discovered. I really found it fun and so fast that I got excited thinking, maybe I really will finish all these projects before Christmas. :-)
But I do have to say I find it difficult also. I just don't have the "creative" gene. I can follow a pattern but when it comes to dreaming up (and executing) something, forget it. Mine doesn't look like the pros or folks that do this regularly but I really enjoyed it and think it looks well enough to give the grand-kids.
Hang in there and keep practicing, I think it will get better.