For the price of new poured walls that are properly re-enforced you could probably leave the Jersey barriers there and put in SAFER Barriers.

Good idea for the turns but the straights need new STRAIGHT, flat, walls or you lose to much of the racing surface. I know, "It's really easy to say if you don't have to sign the cheque." 😀 ;D

I Love the old walls we have now. They're Exciting!  ;D

Be carefull what you wish for. Jersey barriers were origionaly designed to stop crossover accidents and stop vehicles at highway speed from bouncing back across lanes.
I know that some of the divisions are now approaching speeds that go beyond the engineering of the barriers but thats only in certain spots. If you put in straight walls, even a slow speed spin or bump into the wall will result in the car coming back down across the track, and always seems to collect cars handicapped to the back.
Some combination of wall surface might be the solution. All the "launching" has occured going into or coming out of the corners. When the existing wall is hit parallel, it sucks the car into it.

JMO

Its not easy being green... That being said I've seen the same at Flammy on the back straight and they are not jersey barriers