Seeds IV

Well, the seeds are growing, that's the good news I guess. The heating pad did make the peppers pop up immediately so thanks for the suggestion! I have no idea why the two plants in the bottom right (one tomato, one arugula) are growing so much faster and better than the others. I have rotated the box around under the light occasionally and moved all the cans around to try to give them equal access to the light. Also, my lettuce has issues. It is all spindly and falling over like the little stems aren't stron enough (see top right). Anyone have any ideas? Suggestions?

Seeds I
Seeds II
Seeds III