You have a few options pre-DotN... you can play a rune during Upkeep to synch closer to your mount (both rider and mount pay a rune to synch 2 spots closer). As you stated: you can also use contingency. The Fardrengir and other mount-centric dwellers/denizens get Passive powers that allow for better synch and synergy in the upcoming DotN book.
The depth of the rune economy seems to have no end. Now, I see a viable strategy to deal with mounted units would be to always have one dweller force a separation between the rider and his mount in initiative. The rider has to always counter or just deal with the gap in other ways. I love the depth to this.
Cinematic/Generic actions is the big one. People tend to look at their powers as the only thing they can do - a weird sort of tunnel vision. If they get paralyzed, ask them what they want to do and go from there.
The rule of thumb that has been stated on here (and kudos to whoever did, it was good) is "one verb, one rune". So "I leap from the house, run across the field, and stab him in the face" is 3 runes.
edit: you might want to double check over the Upkeep actions. They are easily forgotten as well, though less so than the cinematic/generic actions.
Amplify doubles everything except focus.
Weak defense when attacked from behind. Countered with a single rune, but easy to forget.
Cleanup happens at the end, so sometimes things like Wolf Form, even without the maintain, are useful for that round. An edge case, but my player thought it was worthless all the time if he couldn't STAY in wolf form, and I was like no... you can eat them for a round.
