So what do we know about season 10?
1. it will come with some featured episodes (one as a prequel)
2. there is the sector space revamp
3. it most likely will be the final piece in STOs story arc about the iconians
4. several t5 ships will see a re-release as t6 versions
5. we most likely will get an iconian reputation system
6. probably even t6 fleet holdings at some point (there are countless of small info pieces about fleet versions of the t6 ships so at least a t6 shipyard appears to be a logical addition)
7. there are rumors about the gamma quadrant being added (but i can not really confirm this)
8. embassy sci consoles get a revamp (new versions have hit tribble and from first reports their damage values are higher than the original plasma doping)
9. the STO item system gets a revamp (it actually got it when R&D was introduced but now the old item system will be shut down) -> this might lead to better performances, less bugs and shorter maintenances (hopefully)
10. the [amp] warp cores gets a major nerf
there are several content leaks here: Leaks - Updated Constantly [I.Q. Fleet]