It’s not just the science, although that’s all we’re doing at present on ISS. LEO has strategic importance. The Chinese know that and we used to as well (star wars, etc.).
Well that little USAF reconnaissance orbiter is pretty slick and it has a nice size payload pay and long (2-year) orbital endurance. If you supplement that with 1 or 2 smaller space stations that can go unmanned for periods, I would think that would be enough. The commercial space programs will fill in the larger scale stuff by separating the worlds multi-millionaire adventurists with some of their surplus cash.