Hi. You haven't said what batting you're using - ie: what is the max distance for quilt lines? I always choose W&N that allows for 10". You said you don't like SITD...but how about "inside echoing"....sorry....that's what i call it....like maybe 1/4 - 1/3 inch inside the edges of the envelope and inside the flap ?
I totally agree with you....i have never taken the time to really work on FMQ with my DSM....so straight line things are the way i go....and even though i start thinking about it when i start the quilt, sometimes i'm still puzzling the "how" even when it's been sandwiched.
GOOD LUCK.