The devs should try to model a single player tutorial after the one in MAG.
Go here, crawl under this, jump over this, throw a 'nade at this, shoot this, rep this.

But i think they should use the "future tech" to make the combat training more real.

They could have the trainee spawn in a logi suit with a repair tool and have them rep an LAV thats on fire and use it to drive to a supply depot somewhere on the field, where they would change into an assault suit.
After changing suits they would be directed to approach a null cannon held by (Rather under skilled) AI mercs in different suits so the trainee can learn to fight against them.

After the null cannon is taken you could have a group of (Again, under skilled) red tanks move towards the objective, direct the trainee to move back to the supply depot and change to an AV fit. During the fight with the tanks multiple turret installations could be dropped in allowing the trainee to hack and use them to finish off the tanks.

At this point a blue dropship can do a cinematic landing nearby at which point a 4 man fire team would jump out and direct the trainee to get in (Think Tom Clancy's Rainbow Six Vegas 2). This would would close with a video of a leader form you faction giving a speech (maybe similar to the message you receive when you first play dust now.) at a basic training graduation ceremony.