If they're importing the 5e rules as faithfully as possible you'll be able to powergame the absolute shit out of your character. The current edition is about as balanced as D&D can probably get without completely gutting its magic system and making every class too boring and samey, but it's no where near balanced.

The real opportunity to break the game wide open will be if you can build all your companions from scratch. Just as a crude example, make sure everyone has a Charisma of 13 and takes two levels of Warlock (not at all a hardship, even if your Cha never goes above 13 there are plenty of great Warlock spells that don't rely on attack rolls or saves) for the Devil's Sight ability, which lets you see perfectly in even magical darkness, and you have an entire party that can act at full capability within the radius of the Darkness spell, which is crippling to 95% of enemies.