That's a bot, you can tell by the irrelevant links in their signature. Ignore it.
Your colours are all very... disconnected? There's no harmony between them. Colour theory is a huge topic that I can't hope to summarise in a post like this, so I recommend looking up tutorials on colour theory and colour harmony. One particular thing you should consider is avoiding "pure" hues, always mix some ambient hue into your colours. Instead of using e.g. pure red and pure grey, mix some purple or blue into both, and that'll help the colours look like they exist in the same place, affected by the same light/environment.
You may want to avoid large areas of neon colours, as they're distracting and lead the viewer away from the important parts of the sprite. Neons are great as accent colours, used very sparingly to accentuate important parts of the design.
The characters' arms are different lengths.
Nitpick: Archers don't usually grasp their bows so strongly. When shooting, you want a very minimal grasp to keep the bow steady, and this usually carries over even to holding the bow when not shooting it - they tend to hold it loosely, just enough to keep it from falling out of their hand. Holding the bow like that makes the character look like they're usually not an archer, but more like they're a knife-fighter who just happened to grab a bow.