To give yourself an extra boost in 7th Legion, look at the file called missions.ini in your .\data directory. At the bottom of each mission profile you see a header called 'PVSTART'. That's your starting vehicles. Each number there represents how many of a certain unit you will start with. Be careful when editing this - sometimes (Usually with machine gunners, as far as I can tell), your map will load and a fair chunk of your force will blow up.
Here are a few of the unit places:
(Each number I list represents which number 0 on the list, from left to right. You should have something like 44 numbers there, but don't quote me on that).
1st zero - Ore Carrier
2 - Ore Truck
3 - Crusader
4 - Oppressor
5 - Crucifier
6 - APC
7 - Faith Hammer
8 - Annihilator
9 - Purifier
17 - Mortar Unit
18 - Priest
19 - Medic
20 - Slaven Rider
34 - Inquisitor AC
35 - Revelator AC
37 - Nova AC
39 - Redeemer AC
Last one is your mobile construction vehicle. As for the others You'll have to check it out for Yourself. You can have any unit you like by doing this, nomatter what team you are sided with.
An example for any who don't follow:
The original looks like this: PVStart=0010000000000000000000000000000000000000001
You'd begin the mission with a Crusader tank and an MCV. Let's spike it.
Now when you begin, you'll have two MCVs (Just in case), the wimpy Crusader is gone, and you have 7 Purifiers, 4 Redeemers (For that long range fun) and 8 Revelators (Because they just look so cool). Naturally, you want to send small attack packs with these guys, since they are pretty well irreplaceble, and you gotta love those cards.
You can also change your mission goals, the briefing and some other stuff in that file, though I'd stick to the safe side and just mess with your units.
Remember that if you are reloading a saved game after you've edited the file, you MUST hit escape and go to 'Restart Level' in order for it to work!