well do you want a nice smooth quiet ride with sloppy suspension? or a taughter more precise harder ride?
most cars were designed for the average motorist to go get the groceries, or whatever (minimum NVH... noise, vibration, harshness). not for maximum handling performance. everything is a tradeoff. you take your pick.
think about what you want. areas where you definitely should use urethane are for swaybar D bushes and link pins. also rear trailing arms if you want to put power through them.
i have been bitten by the factory rubber bushes with an old EH i had many years ago. i put new factory rubber bushes through the leaf springs on the back. they only lasted 12 months. the problem i worked out was they were probably made when the car was, and had been sitting on the shelves in spare parts for 30 odd years. they had degraded, even though they were NOS (new old stock). think about when the genuine toyota bushes for your ke70 would have been made before you spend your money.