360 is small, but if you're able to power on and play the game, with the card boosting without issue, you're fine.
There's always room for improvements, like if you wanted to overclock the card or something you'll want more wattage supplied. However if you're happy with things now, don't sweat it. Only worry about it if you run into issues, imo.

Unless you have unlimited money to just throw at the ultimate gaming PC, but you clearly stated the opposite.