2. The trick against Marines when playing Machina is your Exterminators. Take a lot of those. You need to be able to outnumber your ennemies, preferably taking only one target at a time to ensure you kill him. There is no use in losing one exterminator to take a grunt to one HP if he get patched up again and come back on the battlefield two or three turns later...

3. Talking about wounded ennemies, Hunters are really usefull for that task. Rarely used without dying in the early stage of the game because of the grenadiers splash damage, they are wonderfull in pursuing lone targets on their way back home for reloads/healing, or to set an ambush quickly on attacking forces. One of the trick I like best to do with hunters (albeit I do it quite rarely) is to trick the opponent in thinking your hunters are on a side of the map by revealing them only enough so they can't be shot at, retreat them by end of turn and send them running to the opposite side of the map without being seen. Thinking your hunters are still at the first place they spotted them, it is quite rare for an opponent to expect 3-4 hunters taking post shots on the second front and usually end up with casualties on his part or at least some psychological advantage on your part.

4. I find that it is quite rare that I manage to kill ennemies with missiles. When I do, it is either a "lucky" shot behind the ennemy line or because of splash damage. I use MT mainly to "herd" the ennemy where I want them to go, then do hit and run tactics with Hunters and Exterminators to wear them off. While Hunters are quite weak and should be used sparingly (especially against escorted grenadiers), Exterminators are tough enough to eat about anything and be able to walk back to be patched by an AI, including splash damage from one or your own missiles

5. As usual playing Machina, don't leave home without at least one scanner. I personnaly prefer two if I can spare the RP.