When I started out making 3D models for Nordenfelt I made all design sketches, 3D models and rendered sprites public. I thought it would be a clever way to get feedback what's good and what's not. Theoretically not a bad idea. Practically: it was worth nothing.
Due to the fact that I was a newbie game artist back then I was not aware of what's essential for game graphics. Nordenfelt's visual style is "simplified realism", alike Baldur's Gate. So I thought making somewhat realistic graphics would be sufficient. As you may guess the fuzzy word "somewhat" turned out to be a stumbling block.
Whenever I presented an asset people started to argue that the angles of the Gatling guns were not realistic, that steam engines need boilers or that there's no hint how the machine was able to float in the air (e.g. visible propellers). In my naivety I followed these hints and altered my assets for the sake of realism.
I remember having a forum discussion about the cockpit shape of the player ship. A guy argued my design was flawed because there never has been any real-life aircraft with a cockpit shaped like my 3D model's cockpit. That was the moment I asked myself: What does all this not-plausible-in-real-life carping have to do with my game? It doesn't make an iota of difference to the gameplay.
The problem with showing assets in isolation is that the formative design rules are not obvious. Above all assets have to carry the gameplay. If necessary paint tanks and war planes in pink and red if it helps to distinguish them from the background (what would be disastrous in real war). It's irrelevant if propellers are too small to carry the weight of a hover bomber. It's more important that they don't cover other enemies which may become a real threat then.
Finally feedback on assets is just "noise". Everybody has a different taste and idea of what your assets or game should look like. Therefore it's a waste of time to adapt assets to other things than gameplay and overall style. As soon as people see your assets in motion and interaction with each other the scope of feedback jumps to a way more helpful level: how good the GAME is/looks.
Don't get trapped on the details level.