GMzH: Actually, I try to write a small guide about "How to start into a successful vagrus' life". During this I began to wonder about the penalty management for mid-size to large comitati, because - with all polite courtesy - it's not the supply management that makes greater comitati difficult to run, it's the sheer accumulation of (arbitrary?) penalties.
There are at least:
- the new-added licenses for fighters (about 5 Lyrg to 5 Bross per day)
- limited supply stocks at the most settlements (resulting in non-profitable slots with estimated costs of up to 7 Bross per day, however on the long run reducible to an average of maybe 3 Bross per day)
- limited cargo slots, reducing the capacity for supply transport (ditto)
- road taxes (exceeding 15 Bross per day after some time)
- crowded camp (difficult to numeralise)
- conspiring slaves (easy enough to avoid, listed for completeness)
- limited numbers of parallelisable tasks at all (resulting in non-profitable slots, tricky to numeralise at large) and in special due to the reputations system: nearly no parallelisation of profitable jobs anymore when reputation exceeds 2 (as it's not at least the reputation win that adds profitability)
- limited quantities of profitable trading goods (resulting in non-profitable or less-profitable slots, however quite neglectable as far as I see)

Some of the penalties I consider as deep-seated in the underlying world. Others seem more arbitrary, especially the road tax and the cargo slot cap. To a certain degree, I can accept that as a need of balancing. But then again I wonder whether one could try to find other approaches.

To sum up the following text my approach is:
- diversify the money sinks and
- add some sugar for the gamers well-being.

Of course, I don't know whether exactly these things are already planned for later releases...

What is the problem of a rich vagrus?
That he can hire as many soldiers as he like? Of course, that would make tasks easier that are thought to be difficult.
At the moment, the money is simply taken from the vagrus - by the tax, by the licenses, and by bad luck. That works... but it may frustrate the gamer. Is it possible to add sugar icing, maybe?

One thing that came to my mind was the "money-for-honor"-system: when your rich enough, you'll get the honor of financing a war ship for the community. Or in medieval times if you would be approved as a new guild in the town, you have to maintain a slice of the town walls. What could be a task for a vagrus? Maybe being the financier of a part of the imperial road? Or something independent that has to be payed "in public interest", an expedition to some distant place maybe or building up a new fortress.
This should be introduced over time, starting with hints when a vagrus is trading expensive goods: that someone in charge could take a closer look at the vagrus' (financial) means. Because as soon as you can offer silver bars, it's quite clear that you has been able to pay them by your own before. If you offer even a stack of silver bars, you obviously had a well-filled wallet prior to that... Traveling with an astonishing number of fighters does the same, it shows that whoever pays them has to be a quite well-heeled guy.
So you could leave the player a choice: carefully trying to avoid everything that indicates a nice amount of wealth (and thus also abstain from making use from the wealth to ease the vagus' life too much), or... having it taken "for the common welfare". If you ask him to pay for an irrigation plant somewhere and then manage to introduce a new settlement only made available by this new-built irrigation plant, a settlement where you are of course held in highest honor (but as they need all the income by themself up to now, only giving nice words), it would be at least a bit less frustrating as simply be taken in by greedy tax collectors.
On the other hand I know that this need to be coded, tested, balanced, and introduced... However, at least for the beginning it might be possible to transfer more or less everything into pure fiction (referring to some inaccessible areas?) - except the money demand, reducing the work to writing the according texts.
That is: if they can be fitted into the world of Xeryn.

Other options are things in the same line as Fort Larius, but are to be finished with only the own armed forces, too. If there's no further plot attached to it, it will have some arbitrariness, too. But you can at least try to haggle for the minimal losses in combat. And you could be asked by fighters for taking them up to become member of the renown squad that had been victorious at this and that place... sugar icing for a loss of wealth.

A third way is to make the vagrus a (maybe reluctant) creditor. The European Middle Ages offer illustrative material for this. Whoever is assumed to be rich has to lend money to someone who has the means to exert pressure. This is quite near to the tax collecting, but still some differences can be pointed out: the money is promised to be paid back at some time (even if it never comes into reality), the creditor has some important person being indebted to him (even if there will be no option to make any usage from this), and... at least it's not such a repetitive blank extortion. Well, not the first two or three times at least...

GMzH: In fact I also found the comitatus size being a problem.

Only one aspect hereby: There is a time when a vagrus don't has good equipment, his perks are low, other bonuses also have still to be achieved... that's a moment when my first impulse also is to simply invest in "man power". Because it's the only option left: equipment is not offered yet, perks needs insight and insight had to be spend on other things first...
Is there anything I miss? What's the skill either of me as vagrus or of me as player that I am assumed to use in this situation as a working alternative?

Well, for me as a player there is one: an extended saving and reloading management.
I regard it as a kind of 'soft-cheating' as I 'overwrite' the games parameters in this way. But if my comitatus starves I have to reload also, and then I can do it as soon as it's clear that it will be unavoidable later-on with a certain probability. It's less frustrating and faster on the long run.

What I wondered when I bought army licenses was: how big is a mansio? And am I assumed to be the only vagrus with comitatus there? (I have difficulties to guess how many comitatus' you consider active at the same time. If the meetings on the road are an accurate indicator, I probably am the only one in a town usually?)
In Deven and Tor'Zag's Shelter probably space is scarce, and in the quarries even more... So could it fit into the setting that a mansio simply refuses a comtiatus with more than a given size? This could more or less "hard-cap" the crew size. My imagination says that I could let the people outside the gates of a settlement or quarry and only do some 'shopping' inside. But that could lead to tensions in the crew - they will prefer a stop with some variety, I'm sure...
On the other hand, as I said pure man power sometimes is the only option left, so it shouldn't be regulated too strict - in my opinion.

EDIT

Of course, to soften the mansio size cap, possibly first restrict the bonus-giving "comfort functions". At least I would imagine that having a good time is depending on "service personnel" that requires some space for themself, too.

Beasts and mounts could get an extra cap: if I assume a beast of burden needing the space of a car with trailer and a mount at least the space of a small car... 200 mounts would need the car park of a middle-sized shopping-centre? From images I had seen I don't think that real caravanserais had such an courtyard... :-o