The Startup: a player is given a free trader: jump 1, carrying capacity 2. His primary goal is to establish a base in a good location.
So he stakes out a pair of worlds that gets him 2 points income per turn, and builds an Office on one of them.
Over the next couple turns, he improves the office by adding outbuildings (stack them underneath the Office counter). This is the money equivalent -- now that he has an office, he can stockpile. One counter for a Warehouse, two counters for an Office, and three for a Factory. When he needs to, he can liquidate the assets and buy something else.
Then, when he has enough saved up, he adds them to his income and buys a new ship, or, more likely, a small fleet of traders. And he establishes new trade routes, builds new offices, etc.
Given enough time and no competition, he will have a factory on every world that has a significant trade volume, connected by high-capacity freighter divisions.
The Pirate: a player is given a secure trader: jump 2, attack 2, carrying capacity 2. His primary goal is to establish a base on a low LL, high TL system. For the pirate, carrying capacity is always one greater than the counter's face value. This reflects the profit realized from selling what you didn't pay for. (Even minus maintenance, repairs, and fencing, grabbing an air/raft or cutter once in awhile pays many times over.)
Every time a pirate enters a system, then he must roll the Law Level or less of that system to be identified and attacked by system defense forces. Resolve combat using the military combat rules. Anti-piracy come in all shapes and sizes. Attack factor = Law Level. Class A/B: Task force auxiliaries, otherwise single ship.
When a pirate is identified, all of his assets in the system are confiscated.
His secondary goal is to build a web of Informants on target worlds. On each planet he visits, he may spend one point to place an Informant. The Informant requires no upkeep, but serves as an economic enabler: with an Informant, the pirate gets to trade without rolling for the patrol. Unless his primary base is in a system with Law Level Zero or One, it makes sense to place an Informant there. This also means that a risk-taker may risk flying into a high-law-level system once, placing an Informant, then building a base.
A pirate map cannot have more than four Informants in play.
To balance things some, there should probably be one patrol task force (a squadron of type T's) for every pirate in the game. This task force would do random jumps around the map, and act as a kind of roving pirate detector. When they're in a hex with a pirate, the pirate has to roll 8+ (or something) to remain incognito. Being discovered triggers attack from the Patrol, attack from system defenses, and confiscation of assets in-system. How's that for dangerous?
I suppose a pirate's ultimate goal is to build up a fiefdom. Therefore, he may build as many bases as he likes, and may improve them with as many buildings as he likes, but can only have one ship counter (be it a single ship or an entire task force).
At some point, it would seem that he can have so much invested in a world that he essentially owns the world. That means the system defense forces become his. I'm unsure of the broader implications of this. Perhaps that means he wins, and his score should be tallied up.