Overall, I like the set-up!
I'll echo what Alienscar said, in that you are probably planning too much and constraining player choice too much for my tastes. Now I will say that it may well be that your family is accustomed to this kind of set-up (indeed, it isn't dissimilar to a lot of pre-written adventure modules you see around) and all is fine.
However, if I can make a suggestion that will simultaneously give
you less work to do and give the
players more power, then let me say this:
All PCs need in order for an adventure to run is two things:
motivation and
obstacles to achieving that motivation. So, for example, an edit to the set-up might be this:
You've made it as far as Marienburg without the bounty-hunters catching up to you, eating squirrels and drinking pond water for the last two weeks as you cut through dark forests and foundered in muddy swamps. You're filthy, you're broke, and you're desperate--no one is going to take a chance on a villain like you, and you know it. But you've heard of a chance: there's a band of mercenaries, run by some guy named Rolf. Get in the company, and you're safe--the bounty hunters wouldn't dare touch one of Rolf's men. Or at least that's what you've heard. That's what's on your mind as you approach the gates on that rainy afternoon: this. This is your last chance.
The point here isn't the precise set-up, but giving the character immediate stakes--they
need to join this company, because if they don't, it's a short drop and a short stop.
The set-up you currently have doesn't have any real reason for the players to join the company outside of idle curiosity and nothing better to do (and that kind of semi-visible patina of "The DM Commandeth Thee!"). If *I* were playing an evil character (i.e. "selfish"), I can't say I'd be all that enthused to join this company without some good reason.
Now, the reason needn't be the one I've offered. Indeed, I wouldn't even say that all the PCs need the same reason (you could customize a hook for each of them, depending on the characters they're playing), but I think you'll be massively better off giving them a
real motivation to want to join the company.
Now, once you've got a motivation in place, they are going to work harder to get into the city, they are going to be more emphatic about joining the company, and they're going to be more pissed off by the thugs trying to screw up their chances in the bar.
That brings me to
Obstacles:You don't really need to script exactly what happens when players choose particular courses of action. The reason you don't is because players will often choose courses of action you didn't anticipate and then you're stuck with a dumb look on your face and no idea what to do.
What you
should do is spend a bit of time exploring the nature of the obstacles themselves, so that anything your players should what to do will be easy to apply. So, the guards. I'd put it like this:
The guards won't let the PCs inside because they look like wanted criminals (which they are!). They will fight to prevent them from entering, but they can be bribed for (x). There are (y) guards in the gatehouse and the walls are (z) feet high. They have no interest in pursuing the PCs into the countryside, so if the PCs run away or just leave, they'll just sit there in their cozy guardhouse. The players can try and break into the city or, if they wait, a cloaked figure will guide them inside by bribing the guards.
This allows the PCs several avenues of pursuing their goals (bribery, sneaking over the walls, battle) and, should they come up with something weird, you can easily extrapolate. Like, what happens if the bard seduces the watch sergeant? Can the wizard cast Sleep on the guys at the gate and they just slip by? Is there some kind of drainage ditch that comes out through the wall somewhere that they can slip in? Can they stow away in the wagon of some visiting peddler or merchant?
To my mind, the answer to all of these questions should be "Sure,
but..." and then you explain the obstacle they have to overcome to allow their plan to work.
Same thing with the brutes in the tavern (oh, and as for
Note 1, racism or sexism is always an easy incitement to violence. Just have them crack short jokes about the dwarf). Just set the stage and then let the Rule of Cool and the PCs' creativity do the rest. In a lot of cases they're just going to go breaking tankards over heads, anyway, but you never know, so it's good to be flexible.
The way you temper flexibility is with
motivation, which in turn drives them to overcome
obstacles, which then can be used to segue into new motivations.