Since you're covered by a retirement plant at work, and make too much for Roth IRA, then, unless you're Married Filing Separate where the Roth limit is $10k, then you must make too much to deduct traditionally IRA contributons.

So among trad IRA, Roth IRA, and normal brokerage, you're paying income tax up front regardless. But Roth IRA means no income tax on withdrawals, unlike the trad IRA (tax on earnings) and normal brokerage (capital gains tax on gains). So Roth is your best bet here.