Alas... so many books... so little space in the house....
Couldn't agree more - that's why one room of my house has been converted into a library (floor to ceiling shelves on all walls, above the door above the windows and aisles across the width).
Starship Troopers, Stranger In A Strange Land and Glory Road are classic science fiction/fantasy but I do have to agree with those that've said his earlier work was his better.