Our 26 foot is as long as we want. As far as Queen Bed is concerned be aware that a traditional home queen is 60"X80" there are some of the shorter Class C's that have that size but the majority of the Class C queens are 54"X 80" . Besides the obvious fact that a 60" wide queen gives you more room is that if you want to upgrade the mattress any "home" Queen will work. On many of the island queens they are 60" wide but are shorter than a standard or home queen. Now as far as C versus B goes me thinks you are confusing a Class B with a van conversion. Many Class B's are basically the same as a Class C except you do not have the overhead bed or entertainment center. The weak point in most Class C's is leaks in the overhang area. If you do not need that bed area for sleeping or for storage you should be able to find a Class B that fits your needs.
Be very aware that the number in the model does NOT reflect the TRUE length of the RV. the number on our RV is 28 but it is just over 26 feet newer Class C' that have 28 in the model number are closer to 30 feet. Take a tape measure with you and measure the RV and the mattress. IMHO in the length that you are looking for a U shaped dinette will give you more flexibility. As far as slides go we do not want one but if you do go with one make sure that you can access everything with the slide closed. I have heard of RV's that have to have the slide out OUT to access the bathroom, refrigerator or other parts of the RV. Again bigger is better in many things but not a RV. If you want PM me and I will send you links to new class C and B's that fit your bill so you know what to look for in used units. And one more thing I am an even ;larger person than you are so this is not coming from some midget that is under 6 foot
