If I am using Bar End Shifters, is there a compelling reason to change the old brake levers?
Well, you don't have to… That said, Tektro makes some very nice and inexpensive levers – both drop bar levers (RL340) and interrupter levers (RL720) which are much more effective than suicide levers. At the very least, I would take off the suicide levers, I've never had good luck with them. The problem that I had with suicide levers was that they had so much flex in them that it was hard to get good braking unless your wheels were perfectly true and the brakes were adjusted very close to the rim.

Found an extensive discussion on suicide levers here.