Learning the French

[MMFD]

When your composition is mostly vet musketeers and some skirms it's always worth it. It can give you the ranged infantry edge as well as making your anti cav better.
As for upgrades instead of unit shipment it's really situational. In general I'd say send units shipment when you feel behind to catch up in unit count and send units upgrades when you're ahead to outtech your opponent

Yeah, that makes sense. Thanks for clearing that up.