You know the drill commanders, get those files in your installation and be ready to get some tanks off the production line!
Most of the things you asked for are done, especially an easier variant of the second mission. It won't be life-taking anymore to try and set up a base ;)
For the rest, most changes are pretty much unnoticable. For example, I changed Rhiza's defense squads in the 3rd mission. I hope you're happy with this!
Warning! I checked Order land attack squads (Mission 2) to be delayed as they are based on your current situation. Air attacks however are still thrown at you! Be cautious, you are advised to get AA defenses pretty quick if you want to stand a chance :( Use the mass deposit behind Thalia's base to start up your economy a bit.