I have always thought that if the hardpoint in the planet model for exactly where fighters and drones were being released (the stock model has it inside the planet and when launched they collide with the model) was moved to a small distance just above the surface of the planet, that this would fix the problem with fighters and drones being launched from planets.
Another alternative is to actually simply add (create) a squadron of fighters through the mission script that 'appears' near the planet. How many fighters would a whole planet have any? Especially if its a Homeworld? In 20th century terms, if the Earth was attacked by aliens from outer space, how many F-16s and F-18s would the US be able to launch in its defence, let alone the combined forces of the world's airforces? A script cant support 100s let alone 1000s of fighters (the max. ship limit for a mission is 60), but perhaps a timer can be used that generates a new squadron of fighters every 5 minutes.
Using orbital fighter bases is probably the simplest and easiest, but it would be nice to get the planets working as they should. There are some new planet textures that Wanderer pointed out to me on Battleclinic, but overall, planets are an under ustilised resource in the game, especially since we have 9 different types of planet terrains to choose from.