"Some guy who has crappy archers, instead of good solid infantry, isn't going to be of any help!"
That's an actual attitude in this game, and it's part of why the unit type IR exist. For many people, the unit type they recruit is part of their character's identity.
You have to remember that even as a Marshal, it's not your job to micromanage everyone into doing exactly the most militarily efficient thing at all times.
Not quite equal but fair enough.
1) If you notice someone that is lagging, try sending them a message asking if there's a problem, and if they need any help. Offer to help them resolve any problems. Then you can find out why that person is lagging, or only has 5 men, and maybe give them some advice. Maybe you can contact the lord of the RC they are using, and see if you can get a draft.
2) If someone is too slow in their refit, then yeah, you can yell at them. If they are only leading 5 men, then yeah, you can yell at them. You can order them to recruit 20 men and be back in the road immediately. (Be careful with the "within a day" thing, though, as you probably already are aware.)
3) Hand out kudos, by name, to the nobles that make it where they need to be with the required number of troops. Seeing your name in lights is a great motivator.
4) Make sure to explain to your army why you need them to be so fast on the refit. If they know that lagging too far behind is going to cause serious problems, maybe they will recruit from the non-elite RCs so they can to make sure they make it on time. Or maybe they will make sure they are there on time, but with a few less men.
5) Beyond that, relax a bit about whether or not one or two people can't make it back to the rally point on time. Loosen up a bit on the schedule, and urge on the laggers to catch up. There's rarely a battle plan that *requires* such precise timing that lagging behind in the capital for a day means you miss the whole thing.
As for archers.... Good solid infantry is always better than crappy archers. 
The key is to make sure that your realm doesn't have any crappy archer centers to begin with. Only let them recruit the good ones, and you don't have to worry about it.
I am not saying I couldn't take a more active effort on positive things, but I am not yelling at people every turn because they didn't move. In fact I think I have dealt with unreasonable attitudes from others after my laxness, because I have put up with people clearly not following orders for several days and ask them why, then they act like I am crazy/a jerk because I think they should actually follow orders.
