I'm torn.
Angled can be done to avoid the main problem, thrust not agreeing with apparant orientation of the ship.
Combined with a nonorthogonal perspective, it gives you a good idea of what the ship looks like.
Yes, logically, the 'playing field' should also be tilted, ships getting smaller as they go up, etc.
Perspective is an invention.
The egyptians drew battlefields with each figure drawn from the side, but arranged on a field from overhead. Most RPGs (the computer kind) do the 'false perspective', where the figures are seen from the side or 3/4 view, but the area is done as an orthogonal arrangement of tiles.
Personally, I have no problem with the perspective disjoint. I mean, consider... you're not really floating several hundred meters from your ship, watching what's going on. From a game perspective, the playing field is artificial.
Therefore, anything IN the playing field is there for information purposes. The ships could just as well be blobs with numbers.
Angled perspective, then, communicates both heading and shape, giving you a good idea of how big the ship is and what kind of ship it is.
All that said, the point of variable rotation is a thoughtprovoking one. I'll have to test it to see if it jars me, but that could easily be an insurmountable issue. I don't know...
Tentatively, angled makes sense to me, only because I maintain the stance that ship graphics are, in game terms, a source of information, and angled view provides more information.
But, fwiw, I understand the opposite view/taste completely.
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When I am working on a problem I never think about beauty. I only think about how to solve the problem. But when I have finished, if the solution is not beautiful, I
know it is wrong.
- Buckminster Fuller (1895-1983)