Those are both very good points. But I still think it works better dramatically to say that normally any Jedi can block/counter such techniques. The way I see it, if it were that easy to choke, levitate etc Jedi, then Sith would be doing it all the time. Plus, it's more 'moral' that the Jedi's own conection to the Force would allow them to negate any attempts to directly attack them through it.
Back on topic, I think Luke could have a tough fight on his hands here. Both Hanna and Scout have been training since childhood, Luke has what, a few weeks of training? Scout's Force-touch is weak, but one thing she can do well is anticipate (she parried a blow from Asajj Ventress) and she is physically adept (as pointed out earlier). Combined with Hanna's Force talents (described as polished, strong and supple), I think they'd have a good chance against a foe who's still coming to grips with his abilities.