Just a couple of thoughts:
1) On a flex/derated takeoff there is a fair extra margin already gained from the actual temperature being lower than flex temp. (lower TAS), so not doing a 90 degree turn will not be a problem. (as long as the line up is sensible)
2) On a performance limited runway it will be an issue. If you feel incapable of performing a 90 degree turn then adjust your performance to counter the extra distance used in lining up.