Some new sprites I'm working on...

[Vipershark]

Well, I'm going for 8-bit type graphics and charm, but not necessarily 8-bit aesthetics...

I'm honestly kind of confused by this statement.
Considering that graphics are aesthetics, you're going for 8-bit graphics but not necessarily 8-bit graphics.
What? Either pick one or the other.

I don't understand this fascination that people have with making "8-bit" while refusing to take into account the things that make 8-bit 8-bit.

Edit- I noticed in the OP you said that these are simple graphics for a test game so if all they are is temporary placeholders while you play around, that's fine. If that's the case I apologize for coming off as abrasive.
But if you're asking for actual C+C on things you that intend to put in a game that you intend to ship and this is your result, that sort of thing won't cut it.