Tracking error against the index, auditing, security, and financial controls are more important than a couple basis points.
Honestly a much stronger argument is tax efficiency. If you're buying the individual stocks, then even when the index is flat you'll have some capital gains and losses. You can use both these to improve your tax efficiency - the losses can be harvested to offset realized gains elsewhere, while any appreciated shares can be donated to charity and repurchased with new money, effectively increasing your tax basis.
Still, you're likely better off just hiring people to do the tax planning, estate planning, and philanthropic services. It's essentially setting up a single family office with no control over your investments.