Don't need Silo support as then there is no point in killing the Refinery. That's why we rush to get the Refinery first, typically.
The ammo, yes I agree it should go up or !ammo is available after the first vet level only. This stops for ammo at start of maps making a single player able to kill a building (thinking to promote teamwork). As for refill health and ammo, no it shouldn't do that. (Would be same concept as using !char command in enemy base, which is unfair)
!struck would be the same as !ammo in a way. supply trucks are very useful on maps and can change the game quickly if used right . I don't see a use for this command.
Vanq would be nice to go back to 300. They are so fun to use!
Turrets / Guard Towers, I agree the prices should be different if possible. The IK defs are way more powerful then regular maps.
Just my two cents