My first big project! Any advice?

I’m weaving a blanket for my mom for Christmas and I’m super excited about how it’s going! I’m weaving three panels and then sewing them together and I’m planning to finish it with a twisted fringe. As you can see, the warp is striped and the weft is plain white.

I just pulled the second panel (top) off the loom and I’ve found that it’s much longer than the first panel (bottom), and the weft is more pronounced. I’m not worried about the length difference, but I am curious about why the weft is more visible. What did I do differently between these two? When I was weaving, it didn’t feel different. Is it something to do with the warp tension?

Also, any ideas for what I should do with the left over cloth when I cut it down to size? I think I’ll have about 8 by 20 inches, before washing.