I have huge issues as well in spite of 1/4 feet, seam guides, all the goodies. I just don't have that consistency, or at least I didn't on the more modern machines. I've been using old Singers and for whatever reason, I do better. Maybe it's the speed or how the presser foot holds them, I don't know. But I'm not obsessing over it anymore. Done is better than perfect around my house. That's my new mantra!