Does MGT address my main issue with wandering Brokers? As in how does a Broker practice their trade across many parsecs in different markets without intimate contacts and knowledge of those markets?
A Broker imo should be tied to a single system at the most, probably even limited to a single world, starport, or country depending on the factors involved (starport class and traffic volume, local TL, government type, law level, etc).
Certainly not simply able to land on a new world every week and immediately start making deals.
They may very well move to a new world and start working there, but it would take time to learn the local market and traders to the point where they were as good as they can be. And they would be sacrificing their old contacts and such where they used to work. A process that would take weeks at least, probably months. A brokerage firm isn't going to let some new trader come in and start making all their important deals without starting at the bottom*, unless they specifically hired the wonder Broker away from their old firm.
* of course, that may be the tramp Free-Trader accounts
Which raises an interesting side question, why should Free-Traders, here today gone tomorrow, expect decent treatment from the local brokerage firms?
"Of course Captain, we'll put our best Broker on your, 4tons of grains worth some Cr4000. It's not like he's busy wheeling and dealing in MTons of MCr commodities and making the firm real money. GET OUT OF HERE AND NEVER COME BACK YOU IDIOT!"
Allowing wandering PC Brokers is really breaking the system imo. I think Free-Traders should have to do their own wheeling and dealing, and generally take much bigger risks and have a smaller profit margin. They are not Brokers (and shouldn't even be able to easily and quickly hire them, or not very good ones at least) but traders (small "t" more of a bartering skill).