There are ways to exploit planets, moons, and asteroids; there should be a way to extract resources from stars.
“Starlifting” could yield any of the existing forms (Isotopes/Fuel Blocks/Et Cetera) of:
Hydrogen
Helium
Carbon
Nitrogen
Oxygen
As well as trace amounts of heavier elements (Tritanium, Pyerite, Mexallon, and some of the refined moon ore materials)
Though adding a raw form that can be refined into the previous materials may be another approach.
The resources that can be acquired from each star should change based on size, temperature, and metallicity (Determined by both the previous two statistics and the types of planets in orbit (not causal but they are related so a good way of determining it retroactively))
Star mining could be implemented in many varying ways for example:
Generating gas clouds similarly to moon drill asteroids.
Resource over time with differing resource concentrations based on the modules used, perhaps with charges that get damaged over time and lose potency.
A station heat mechanic requiring coolant to be cycled between the station and radiator arrays further away from the star (Resources cannot be acquired while the station is above a certain heat threshold and acquisition of resources increases station heat.
Random (Modules could change duration, prediction, size, and frequency) solar flares similar to ore anomalies.
“Realistic” Starlifting utilizing an array of orbital stations (around the equator of the star) and statites, creating pools of plasma or gas near the poles.
One of the benefits of implementing any method that generates gas clouds is that it adds a lower risk lower reward version of gas mining.
Additionally it can allow for more granular uniqueness between systems and regions (Star compositions) in addition to the existing more widespread differences such as ore distribution.