The artillery piece is a valuable unit but does have its drawbacks, such as mobility. However, when playing as the Americans or the British, infantry and artillery are always the more valuable purchase over inf and arm because you don’t need a lot of mobility when moving from Western Europe to Germany and fighting in that theater.
Hmm, I don’t think you’re right at all. Infantry/tanks are better for the UK/US because they have a limited number of troops that can get into action, thus you want the best units going into transports.
The thing you probably don’t realize about art/inf vs tank/inf is that art/inf have a worse “skew” effect. The skew effect is when you lose units during combat that affect your combat power. If you attack with 4 inf 4 art for instance, and you lose 4 units in the first combat round, your attack power has decreased 8 points because those infantry are actually attacking at a 2. With an attack force of 4 inf 4 tank, however, your attack power only decreases by 4 points since those infantry are just attacking at a 1. It’s pretty clear to see what 4 tanks are better than 4 artillery on their own. Plus, tanks/inf have better defensive qualities than do artillery.
Also realize that the UK can only deploy 8 units out of the capital, and you will probably be making at least 32 IPCs which fits 4 inf 4 tank. For the US to utilize the economic efficiency of artillery/inf would require a larger transport system like a 5x5 or 6x6 which requires a ridiculous number of transports.
Art/inf are the best economic purchase for Russia/Germany because they have a ton of room to mobilize units (thus the money saved on artillery can be used), but packing transports requires tanks/infantry for the UK/US, and Japan is relying more on tanks/inf for blitzing beacuse of how long it takes to get to Moscow.