Ambient temperature has a big impact on rise times. How cold is it where you're doing the rise?

Also, you can tweak your hydration numbers. Standard French bread is always at 60% (i.e., for every 10oz of flour, 6oz of water). When you go to a higher hydration, then you've got more water that becomes steam, and that steam powers the "oven spring" that gives you the extra loft you really want. (It's extra important to properly "slash" your bread, so the steam gets out in stages rather than building up in big bubbles then blowing out anywhere it can.) Note that higher hydration turn dough in to a sticky mess. I don't usually go beyond 70%, and I use a ton of bench flour to coat things to keep them from sticking. That means my final hydration isn't going to be quite as high.

Anyway, don't stress out too much about not getting a light airy loaf. If you really want that, don't do sourdough. Use commercial yeast, particularly with the "no knead" method. That gives glorious air.