Now your canvas is stretched and you (hopefully) have tried painting on the unprimed but "shrunk" canvas. (I do it with watered down acrylic paint). Did you leave any raw pieces of canvas, unpainted? Does it look like a watercolor? You can draw or paint into the spaces now they are dry if you like.
Often I will choose this point to create texture on my canvas applying modeling paste (usually) with plasterer's spatulas. If you use a huge spatula and angle it you can get wonderful sweeps of paste that go "dotty" at the end as your paste is almost done. You can draw squiggles and lines into the wet paste. Then I go and play with another canvas while that one is drying, which can take a while.
You could apply a layer of gesso to a canvas to make it less porous. It can still breathe with gesso on it, but the paint you apply on top "goes" further and doesn't just disappear into the canvas. Apply the gesso in two thin coats diagonally onto the canvas and let it dry before you do anything else with it.
Washes on a canvas with gesso on it react differently. An ungessoed canvas wash can be directed by a finger nail leading it along, whereas I find a wash on a gessoed canvas less controlable. But perhaps you're ready to attack a canvas with lovely thick luscious acrylic paint now. Everything and anything can be attached to your painting; and if you seal it below and above with acrylic paint it will last forever, as it is encased in a plastic. (Try it with veggies). Go to it. Do whatever you feel is right at that moment. Be directed by your canvas, not what sells or what someone else did. Be your own person and allow your canvas to be itself; above all, have fun.