Your strategy look pretty viable. That's probably what i'd do being on a rookie team with low ressources/experience.
Basically you want to grab balls and interact with defenses using 2 different "arms". Do you think a single, stronger mechanism could do both tasks? Could you also find a way to score low goal with that same mechanism? There is so much stuff to think about
On a final note, keep in mind that a simple robot who does 1-2 tasks very well is better than a complex bot struggling at doing everything!
