Big update today. 

V0.11 Introduces our new damage system. We now have varying damage, critical hits, and great feedback for the user in terms of eye-catching damage effects! 

The new damage system adds a lot of flexibility and will open up more possibilities for expansion going forward. This will allow us to integrate new weapons more easily and make each one feel a little more unique. Under our current system, the rifle has a greater critical chance than the shotgun, but the shotgun still hits with a lot more individual pellets. 

Enemies can also critical hit you, so watch out. They can chew in to you if you're not careful. 

At a much later date when more systems are finalized and content is getting closer to complete a couple of balance passes with feedback from the players will be made.  So what you see in terms of effectiveness and power for each weapon is probably not representative of the final state of things.