[DonRotolo]

Start by identifying CAPABILITIES. What must the robot be able to do? Not how, just what. Here's a basic list to get you started:

1. Drive on carpet
2. Push a ball
3. .....

OK, once you have your Capabilities, identify a MECHANISM to accomplish each Capability. As others have said, focus on consistency, simplicity, robustness, and repairability.

It needs to do whatever it does as well as possible*, every time. If it does it perfectly, but only half the time, it's garbage.

It needs to be simple enough to build by your team. A completely autonomous helicopter that carries balls sounds great, but can you build it?

Once you do build it, do it well. Use strong enough materials, and if you cut something and it's not right, do it over, don't use garbage on your robot.

And last, make sure you can get it apart so it can be repaired, Don't bury the Jaguars under 2 feet of welded aluminum...

Your mentors are great resources for "vetting" (checking the validity of) ideas. Do that.

If you run into problems, (weight, time, etc) start dropping Capabilities, least important first.