The problem is not the assault rule

[John Given]

I like your list except maybe for the vehicles. They typical tank only had a short-range radio designed to talk with their platoon/company. They weren't typically tied into a larger radio network. Command tanks (not sure if it was platoon, company or battalion level) did typically have longer range radios for talking with higher command. So, it might be better to limit arty to armored leaders (particularly the new leader in a tank) or HQ tank sections, similar to the infantry.

Very good point - I was aware non-command vehicles had only short-wave radios, but they could radio coordinates up the chain of command. Still, you have a point.

If it were up to me, I'd probably not give HTs the ability to call in arty. I am not sure that they even had radios, and they were probably not tied into any sort of command net if they were. It would make the most sense that they would rely on the attached infantry to make those sorts of support calls.

Check this out: http://en.wikipedia.org/wiki/SdKfz_253 Many different types of halftracks carried radios. I think the only exception would be the pure transport halftracks - the unarmed and unarmored ones.

I would think recon vehicles could call in artillery for the same reason tanks could - radios. I made the reference to the Psw 221 because the above FO halftrack is fully enclosed and has a smaller profile, yet is only armed with a machine-gun. This would discourage players from using them in combat, it would seem to me.