If you think your current tax rate is lower than your retired rate, definitely put money to Roth.
Another consideration is the amount you are actually putting to the account.
Say if the total limit is $30000. For pre-tax money it is $30000, but for Roth, it is after tax money so $30000 could equal to $30000 /0.8 = $37500 if your current tax rate is 20%.
