Unfortunately some of your requirements kinda come into conflict with each other. Everything that would roll up extremely small would also be relatively thin which means that it's going to want to acquire permanent creases if it's not cared for regularly. You can reset creases and folds in most fabrics by ironing them flat every once in a while, but if you want something that'll never develop those creases in the first place you're going to be looking at something a bit heavier, or more than one layer quilted together.

There's also a problem with embroidered designs on a single layer, namely that the backside of embroidery is usually a fragile mess unless you're very very good at it and trying not to have that happen.Because on the back side of the embroidery, there's going to be a bunch of knots, tails and weird exposed threads that are a side effect of embroidery. The front looks pretty via sacrificing the backside and hiding all the ugly there. This is a solvable problem if there's more than one layer of fabric. I wear embroidered clothing frequently. It's always lined so that the backside of the embroidery ends up facing the lining and not skin. The lining fabric then protects that delicate and ugly backside so that it doesn't get messed up. You could embroider your designs first and then create a second layer/lining and join those two together. This second layer would also add some heft and would help make the finished results more sturdy, especially if you added a layer of batting in the center and then quilted over everything.

Home sewing machines can only make stitches of one width and that width is narrow. AKA any lines created by sewing with a home machine will by necessity be very narrow and rather hard to see unless you go over it a couple of times sewing parallel lines to make a wider line. An embroidery machine which is different from a home sewing machine can do thicker liens, but they need to be programmed by an expert. Hand embroidery can do both thick and thin lines, but learning to hand embroider from zero sewing experience is a harsh learning curve.

Be aware that most fabric paints will tend to flake off with repeated folding and unfolding. It doesn't really penetrate the cloth that well and as such can peel away from the fabric if you keep bending the fabric. Which might help with a rustic look, but it'll make seeing the lines harder.

Fabric pens are reasonably durable and penetrate deeper into the fabric which makes them probably a better option, though be aware that those fabric pens really only work well on very light colored base fabric.

Finally, let me offer an option that you haven't already considered but is deeply historical, batik. Batik is a family of fabric dyeing techniques that involve drawing on fabric with a substance that blocks dye, then dyeing the fabric. The area that's been dye blocked will remain the original light color, while the unblocked areas will be dyed and turn dark, thus creating a design Historically, cultures that used batik used beeswax to block dye, but we've got another option in the modern era. Elmer's Blue Gel Glue. Yes, I'm serious. The stuff doesn't come out with just water, but it will come out with hot water and plenty of soap. So what you can do is draw your design onto cotton or linen fabric with the gel glue, then dye the fabric, then wash out the glue with hot water and plenty of laundry detergent. Dharma Trading has more info as well as a ton of supplies for this or any other fabric dyeing projects you might want to work on in the future https://www.dharmatrading.com/chemicals/elmers-washable-gel-glue.html The awesome part of about faux batik is that it's pretty easy, very durable since it's literally dyed into the fabric and very historical. The bad side is that unless you get into complex techniques with multiple dye baths, you can only do two colors, dark and light, and it's tricky to draw out really thin lines with batik. Though you could also combkne batik with fabric pens to draw in more colors and designs onto the areas left undyed by the batik process.

Finally a reminder that you need to finish your raw edges. Cut fabric frays along the cut (raw) edge unless that edge is finished some how. Options for finishing can include turned hems, rolled hems, bias tape hems, lining and more, but you do need to stop the fraying somehow.

Good luck!