New mattress recommendations for not petite people?

We added a good foam topper, about 4" thick to the mattress. That made all the difference in the world. I think we got it at Sam's Club. The topper was longer than the RV queen but they are easy to cut to fit. The additional height of the bed we had to get a small step stool for my wife to get up into the bed. My wife and I are also not of the petite group.