Advice Needed: Class A for a large family

We are a family of 2 adults and 7 children age range from 8 months to 13 years. 3 boys and 4 girls. We want to full time next year in June and just returned from a 6 week trial run in our state. We have a 38 foot Travel Queen that we turn into a bunk house at night. Our budget was pretty small and that is why we purchased vintage and used. We have a 15 passenger Ford E350 van that we drive when we travel. We do not tow. I know our gas consumption is higher but it fits for our family. We also try and limit our travel times to 2-4 hour on moving days. Our 6 week experiment turned out very well for us. It was tight, there are no slide outs on our rig but still good. We also home school and we utilized the facilities we were camping and for the most part it worked very well. We bought our rig on Craigslist and while I did get some surprizes that were not disclosed to me, we had budgeted a cetain amount for repairs. We are looking forward to June.