I would start with treating the upper and lower corners of the room. Eliminating Echo slap will provide significant reduction of artifacts.
I was in a reverberant space years ago with high ceilings and many corners. Even using the very small and thin Roomtune corner traps fixed a tremendous amount of the problem
As suggested already, curtains over the window is a no brainer since it will be aesthetic as well.
A nice Persian rug looks great and may help.
With those basics done, you can listen then decide what other areas to treat.
As mentioned, you should get the speakers away from the rear walls.
If you end up with decent results, then consider upgrading to a more appropriate speaker. No use doing so unless and until you improve the room.
.
I was in a reverberant space years ago with high ceilings and many corners. Even using the very small and thin Roomtune corner traps fixed a tremendous amount of the problem
As suggested already, curtains over the window is a no brainer since it will be aesthetic as well.
A nice Persian rug looks great and may help.
With those basics done, you can listen then decide what other areas to treat.
As mentioned, you should get the speakers away from the rear walls.
If you end up with decent results, then consider upgrading to a more appropriate speaker. No use doing so unless and until you improve the room.
.