You can probably go with a 6 flow without worrying about dry times. Keep doing your dry passes the you are doing it. Instead of a single jet, maybe go with a 2 jet wand. Even something as simple as a aw29 will work awesome. A better wand with a
glide will give you better performance. Look at pmf wands. An s bend will be a little more versatile. The 36 blower is small but is capable of 270 cfm at 14 inches hg. Just make sure your seals are tight and the vac relief valve is bleeding away cfm. Check at your truck with your hand over the vac hose and see if it pops off at 14 inches. If not, adjust it until it does. You will give your customers a deeper clean with about the same drying times.