First of all, I feel there isn't much of choice when it comes to missions, realistically there can only 3~6 of bounties that can be taken at a time, and similar amount of exploration, both can be less with choosing who to fight/who to help.
Since it's like that, for me there is not much of "planning" I can do when it comes to hyperspace travel, so it really doesn't matter if I know which direction slipstreams are going.
Additionally, even if I managed to utilize it, it still hurts me when I try to go back, which makes slipstreams negate itself.
And then they doesn't always go for the location I'm looking to.
For my feel, shortened hyperspace travel due to the slipstream happens really rare (which can be rather small bonus because it's usually short or goes weird direction), yet the amount of forced emergency burn because of crossing slipstream is so much, I don't know if it's bias on my side or I'm actually getting lot more hurts than benefit in this situation.
Wish they will be either less hindering to cross, or much more rewarding to use (I don't know how to make it rewarding though).