You do not need to kill the french destroyer+cruiser. These usually score 1 hit on average if you attack them. So, at the very least, you save 6 IPC for a submarine.
You do not need to kill the french Infantry+Artillery in South africa, saving you 1 Infantry in the process, worth 3 IPC. Additionally, you can send the Italian troops (or German) to the Eastern Front 2 rounds faster.
You do not need to kill the french infantry in North africa. Each of these has a chance to kill a unit too, and additionally it forces you to send a small army that way, if you want these territories (you can’t just walk there with one infantry). At the very least you save 1 infantry here too, which would otherwise die, for another 3 IPC.
You get 3 (!!!) Inf for free in north africa, which is worth 9 IPC. And we are talking about 9 IPC spended in north Africa, where you normally need to use transports. Which is not always possible when UK has a strong fleet / airforce at Egypt.
You get another free inf in Syria, worth again 3 IPC + 1/3 chance of losing another infantry.
You get free blockers at South france, if the Allies are at Gibraltar with their fleet and threatening Rome.
So, at the very least you save around 25 IPC, get free blockers for Rome and you can speed up the attack on Russia or Egypt. For the cost of 3 IPC per round.