Too much height can crowd the back-sleeping setup.
Weight and tuck change the feel quickly.
Try a low folded blanket under the knees if it feels comfortable.
Pillow height
A very tall pillow can make a back position feel crowded. A very flat pillow can feel too low. Many back sleepers prefer a pillow that fills the space without forcing the head forward. The exact feel depends on mattress surface and pillow shape.
Even bedding weight
Back sleepers may notice top-layer weight more because the blanket lies across a broad surface. If the bed feels heavy, try a lighter comforter or loosen tucked corners. If it feels exposed, add a thin blanket under the comforter rather than switching straight to the heaviest option.
Leg comfort
Some people like a small pillow or folded blanket under the knees for a more settled feel. Keep it low and easy to remove. The point is to make the position comfortable, not to create a complicated setup.
Surface stability
A mattress or topper that makes turning difficult can make back sleeping feel stuck. If you feel trapped by a soft surface, test smoother sheets, a lower-loft topper, or lighter blankets before blaming the whole bed.