My understanding is there are set jump points in every system, sort of like on/off ramps on the highway. Sure you can try to jump from another location within the system but it is much more difficult. That is how I run it in my games. It's up to the PCs to decide where and how to jump. Using a pre-established route gives you easier checks and less risk, going your own way is much more dangerous.

The way I understand it highly populated systems typically have standard arrival point to make traffic control easier but modern navcomps can usually safely plot a jump as long as they aren't in a gravity well. And that's actually a safety feature rather than a limit of the drive to avoid flying into a star or planet.

I've always thought it was because there were few safe, mapped hyperspace lanes and arrival points, and unless one wants to fly right through a star or bounce too close to a supernova, your only bet is to stick to the designated hyperspace lanes.

From what I understand there are literally thousands of hyperspace routes and that's not counting the secret ones various groups know of, and even the rarely used ones take a few years of disuse to become useless once charted while the main ones are basically permanent barring major disaster. That was what made the modern navcomp such a big advantage when the Old Republic had it but their enemies were still depending on the old jump beacon networks.

But once modern navcomps became common blockades became much more difficult to maintain because if the blockader blocked one route the blockade runners could just switch to another. So to blockade a planet a fleet needs to either prevent any ships from reaching any safe jump zone in the system, and my impression is that such zones are both numerous and very large, or have enough ships stationed near the planet to be able to intercept any ships which take off from the planet's spaceports or to engage any ships heading to those port or another landing area. Honestly given what we know of Tatooine blockading it must have been a nightmare of epic purportions.

I don't necessarily agree. I think that it is entirely feasible that planets like Tatooine and especially Hoth would only have one safe arrival/departure jump point.

Yeah, Hyperspace is finite and limited. Its not everywhere.

Its very possible, if not certain, that any particular planet may only have a couple stable jump points. Especially planets out on the fringe.

Everything I've read on the subject says the difficulty of finding safe routes is linked to the density of objects with enough mass to produce mass shadows in hyperspace in the area and the areas you'll be traveling through which leads to things like travel between Tatooine and Alderaan being faster than say traveling from a star on one side of the Deep Core to a star on the opposite side of the Deep Core because there are so many objects producing mass shadows near each other in the Deep Core that finding safe routes though the Deep Core is such a nightmare that usually its faster and safer to travel around the Deep Core rather than through it.

And I've never seen anything stating that jumping to or from Tatooine is unusually difficult. It might be but I don't recall that fact ever being confirmed, or denied either way.