I'm not a huge Star Wars buff, but from what I understand - objects that are too small to cast a significant mass shadow do not effect hyperspace travel. Even aside from that, hyperspace lanes are huge - the odds of two ships being in the same space at the same time are so remote that they're practically impossible.
I'd bet that the far greater, but still mathematically remote, possibility of a collision occurs when the ship is accelerating/decelerating to/from hyperspace, in the immediate orbit of a planet. Even still, you could fit 12,700 Star Destroyers side-by-side across the Earth's diameter. Even if hundreds of large ships are arriving every hour, the odds of them colliding are extremely remote.
There's actually a scene in the preview of the upcoming Luke Skywalker novel where a Star Destroyer comes out of hyperspace right on the inner edge of a solar system's designated safe hyperspace drop out zone and has the equivalent of a fender bender with a freighter that is part of an outbound convoy as it decelerates.
Isn't the Straw Wars Science: You are in hyperspace and go too close to a mass you drop out of hyperspace?
In TCW S1E4 a ship in hyperspace crashes right into a planet. Also, in S1E13, a ship enters hyperspace inside the atmosphere of a planet then later (their navicomputer was damaged) is about to crash into a star. The ship has to cut off all power to exit hyperspace. So, it appears to me that being dragged out of hyperspace due to a mass shadow has been retconned away. However, in that same episode, the ship was able to detect the star far in advanced of crashing into it, so should have been able to avoid it if their navicomputer was working.
Taking a vector and extrapolating a likely destination seems perfectly reasonable.
Except Obi Wan exits hyperspace in the exact same spot that Jango did. He couldn't have predicted that.
That would create a situation that makes you question why the Falcon wasn't followed into hyperspace when leaving Tatooine by some sort of armed shuttle or gunboat with a hyperdrive,
The Falcon was followed into hyperspace. However, since the Falcon didn't have a homing device on it, the Star Destroyers had to follow closely, allowing Han to realize he was being chased and evade/outrun them. Hence the line, "I told you I'd outrun them."
1 As I mentioned before there is nothing preventing a ship from traveling through Hyperspace in a mass shadow. However there is a safety system built into hyperdrive and nav systems that usually prevent such activities.
The Malevolence's Nav system had been sabotaged and reasonably disabling the safety would have been part of that sabotage. The Consular had been damaged so its not unlikely that the safeties had been disabled on it as well.
2: Perhaps the courses of Slave One and Kenobi's Delta-7 were plotted to point at Genonosis then they just let the safeties pull the ships out when they got too close to the planet's mass shadow.or that of the star. Legends/EU implies that this isn't an uncommon means of plotting hyperspace jumps to systems.
3: Nothing in the movie confirms that the Falcon was followed into hyperspace. Yes Han mentions losing the Imperial ships but that could just as easily refer to having escaped the Star Destroyers by jumping to hyperspace. And I know that he stayed in the cockpit for a while after the jump but A: Perhaps rather then jumping straight for Alderaan he jumped to a waypoint either seeking to shake off any pursuers, or just because the course to the waypoint was simpler and thus faster to plot then a direct route to Alderaan. or B: He was concerned about the possibility of Interdictors being deployed to cut their route off and said that after he felt that they were a safe distance away from any likely points for such craft to be deployed.