I am doing FMQ now for the first time. I'm thinking that there will always be uneven stitch lengths on these quilts especially for a beginner, and it obviously takes practice. I think the secret is to not be too particular especially if it is your first time trying it. If you look at the over all picture as I have I'm sure you'll find the over all look of the quilt is still good.
I haven't tried not lowering the feed dogs. I can't understand how that would work. Doesn't it still pull the quilt backwards?