This is a game idea from aroun 1997, created while sketching during school lessons, playing Master of Orion 2 and reading some stuff about 3D Graphics on flipcode.

Description:
Focus is the construction and setup of space ships and fleets and fighting battles with them. The backdrop could either be a Master of Orion like game or a automatic tech-progress and story based missions.
Ships are constructed in a 3D isometirc view from structural elements (e.g. backbone, beams), crew area (e.g. bridge, living quaters, stations), functional elements (e.g. sensors, engines, power supply, pover lines), armor, weapons, … which are represented by modules that are linked together. The linking and location  determines  e.g. stability, power supply.
Fleets are setup by placing individual ships in a 3D isometric view (with a fixed horizon plane , like in Star Wars). For each ship a defensive and offensive positon and behaviour may be set.

During battles the player gives movement and attack orders to the individual ships. Typical maritime orders like e.g. full speed ahead are used. A battle is controlled by point and click. Direct clicks on objects and an active horizontal level linked to the current object are used. Keys change the active horizontal level for advanced commands.
The ships show damage on single modules and react fake-physically on structural damage. Functionality of individual modules is simulated too.
Control of the player could be on different levels for different ships e.g. full control for the flagship, less control on other ships.

Visual:
A panable and zoomable 3D or isometric view of the battlefield with fixed horizon and orientation. Ship damage and map overviews in schematic style.

Inspriations:
Master of Orion 2, C&C1, Star Wars space fights, other galactic civ games, Sim Tower, Silent Hunter