Nahh, no need to tear all down. Just good calculating with spreadsheets.
With my new plan I will need 10,8k supplies per hour doing 3h manufactoy cycles and 7,2k per hour doing 9h cycles (including supplies for troop training) and I will produce 15k(100%)/18,6k(125%) supplies per hour in 1h cyles, 9,6k/12k in 3h, and 5,5k/6,9k in 9h, so it should be sufficient
At the cost of -20% marble and silk production, -17% gems gems production and 12 less slots for the barracks queue.
Only buildings I need to sell are the manufactories and some small armories and I have to upgrade 2 of my small armories a little and build 6 new workshops and a garden.