New to pixelart, having trouble making my sprites look good and consistent.

[doodoopixel]

So I am making a 2d top down isometric game where you play as a character inside of a computer. The enemies are folders, icons such as the Installer Wizard icon, the speaker icon, etc. I am very unhappy with the "ridgid" look to my pixelart. The sprites are sized around 32x32-64x64. So yeah, I have no idea what to do. Here are some examples of the sprites:
winrar enemy:

Installer wizard enemy:

facebook like enemy:

Folder enemy:

Paintbrush enemy:

Speaker enemy:


So, yeah, I am just really unhappy with the inconsistent ridgid look to it. any advice will help.

[dpixel]

The light sources seem inconsistent.  You have some banding on the folder, paintbrush, and speaker.  The facebook thing looks kind of flat.
But yeah.  They look very much like icons, which are kind of rigid.  Try picking the same light source for all, then see how they look and then try to introduce some character to them.
I like your idea though.

[SteamCaptain]

If you want to go for consistency, try giving all sprites the same outline thickness.
The installer wizard enemy also looks more complex then the other enemies. Try making it just the screen, so all enemies are single items. (except if he's a boss character!)
(Like dpixel said, lighting is an issue as well. No more mirroring for you  )

[Decroded]

u should make Clippy   the end of level boss.