That's not a bad start for your showcase, but here's a bit of pointers to help you for the game:
First have the weapons face in one direction or at least in a manner that will be effective. For example, if you take a look at Absolute Chaos from BBEANS5 (or any of the HS's), you can see that the weapons face in a direction where they attack for a specific bot type or used effectively. Secondly, try to attach the weapon motors and drive motors on a SnapperII so that you can have more weight to spare for better components for a HW. Thirdly, you should shrink the chassis to where everything is airtight and you can again, lose weight and use it effectively. Lastly, upgrade the batteries to two SuperVolts. One pink will NOT last have you last long enough in battle.
Those are some tricks I can give you if you want to improve. I just hope you understand some of these concepts for improvements. There are also a handful of techniques that you can use to improve at the Beetlebros website. Here's a link in case you haven't found it already:
http://beetlebros.gametechmods.com/ra2techs.htm