Higher space altitude or real zero-gravity space, please.

You guys tried using a mip-mapped pregenerated 2D-texture image of the campaign map when at (very) high altitudes?
The picture above has a lot of vertices, terrain and waves, all drawn at the same time I assume.
Can the drawing of vertices not be skipped and simple 2D image(s) shown instead and the waves just values processed by the cpu and only those around a small area around the vessels and not the entire
ocean. Only terrain height values near the vessels and for line of sight for targeting and munition path.
And that would only be required when vessels battling each other on the surface and/or surface to air/space battles simultaneously.
Battles in space only would even need less cpu.
Some nice ascend and descend transition graphics and cinematics and start drawing real vertex terrain at certain lower altitudes again (maybe set by gpu capabilities)
I hope you guys understand what I mean?
And zero-gravity and no planet render, for all I care a nice sprite of a distant looking planet, less cpu cost. Space and space-battles only.
Cheers,