Don’t be over-dependant on defense, tanking is not viable if you get hit by stuff all the time. You can use Beetle Armor to protect yourself without sacrificing too many accessories.
Use the protective beetles to be able to flee/dodge or land big hits without taking too much damage.
Remember to act careful when your beetles are regenerating, though. For that, you can use weapons like Bubble Gun or Crystal Storm to not let your opponent finish you off with strong close-range attacks.