For example, presenting the machine gun guard tower upgrade at the first base in cam1a instead of the third base, will take the edge off of D type players who initially have no defensive structures to start with, while also preventing skirmish attacks from the enemy when amateur O or Z type players underestimate their unit strength after encountering the scav guard towers and lose their initial 4 tanks.
If the first and third upgrades were switched, people wouldn't get the mg bullets upgrade and its two subsequent upgrades until after they get flamer at the second base, encouraging them to try flamers to test their effectiveness. Currently, the mg upgrades are the first presented in normal, and can be upgraded 2 more times, which kind of breaks the mission flow.
Small correction currently this is the order that you get tech on alpha 01
at the first enemy held oil well you get the following tech: Hardened MG bullets, APDSB MG bullets, APDSB MG bullets mk2
At the first base and the second oil well you get the following tech: Flamer turret
At the Second base you get the following tech: Mg tower
At the final base you get the following tech: Engineering, Tank trap, Mobile Repair tech
With regards to what you are suggesting I would in fact advocate something different at the first oil well give players the artefact for
Engineering, Tank trap, Mobile Repair tech
Then move the MG upgrades to the final base and leave the rest where it is. why I hear you ask simple really if you want to defend your base you are actual better not to use Machine gun towers.
I know that might sound counter intuitive but there is some reasoning behind it, for a start units will get stronger as they rank up, not only will they deal more damage but they will take less damage as well. Second towers can easily be by passed mobile defences can't, Third mobile units are more resilient especially when paired with a couple of mobile repair units and mobile repair units can be made to repair them selves by setting them to hold position which makes for a more sturdy and efficient defence.
This is in fact how I defend my base on alpha 1 and 2 I set about 5 or 6 units to do or die and then i have them hold position in a choke point so the computer can't get around them I then pair them with a couple of mobile repair units which are also set to do or die and hold position.
I've tried using towers in the past and found them to be ineffective they just get blown up to easy even when I leave a couple of builders near by to repair them, and what I have found is that its actually more efficient to use units as guards because i have found when using units i only need about 5 or 6 on average especially if those units have some rank on them, but when using towers I need about twice that number, but more importantly scav's out range your units and towers which renders towers useless.
To be honest in the entire game I only use turrets to defend my base on the final mission of the beta campaign and on the level where nexus mind controls your units and structures on gamma campaign other then that I never use them instead I'll just use mobile artillery and vtols to bomb the opposition into submission long before they get anywhere near my base and I'll have mobile AAA units in place to shoot down there VTOLs if they try to attack my base that way.
one suggestion i would make if you are going to switch round when you get various bits of tech is move the pepper pot mortar to say alpha 08 the same time you get the bombard because currently you get the pepper pot mortar around the same time you get ripple rockets which means that its automatically obsolete as soon as you collect it but on alpha campaign the pepper pot mortar might actually be useful for a few missions before you upgrade to ripple rockets or howitzers on beta campaign certainly it would be useful on alpha 12 and would make clearing out all there turrets much faster as bunker busters can't hit most of there turrets.
Also, IIRC, busters could not target non building units in the original. I feel like that's more of a bug, and it should be brought to the attention of the bug group.
I'm not so sure about although to be sure that I'd need to load up v1.10 the last release made by pumpkin and test if that is in fact the case because I'm fairly sure bunker busters can auto fire at units on the original game.