[X] Duty
[X] Community
[X] Knowledge
I don't think freedom is the best angle? I mean, looking at her right now, she seemingly HAS freedom already, so why would she want it desperately enough to go to the Colleges? That's my take anyhow, could be missing the point entirely, lol. She definitely has a want for something more in her life, maybe duty's exactly that.
Freedom is addressing her concerns, as Spätin brought up "signing away her life" as an example reason of why a purely hypothetical Witch wouldn't want to submit to the Colleges.
Freedom is therefore going "It wouldn't be like that, you'd still be free to travel wherever you like, and accept work from a multitude of clients that aren't the army or otherwise find ways to pursue your own interests"
The "more easily than the vast majority" bit refers to how Wizards have more easily accessible means to travel far and wide, and more resources to put towards pursuing what they want, as the argument for why this is an improvement on what Spätin is doing now
It does sidestep having to give up a few years of your life to apprenticeship first before you can actually attain that sort of freedom, but Markus is trying to make a sales pitch here so he's not going to dwell on that
Giving my thoughts on the other options...
I'm leery about Duty, because yes, there is indeed
something there
But it's a something that Markus has no real understanding of
It's basically just him going "Well there has to be some kind of motive for you helping me, a Witch Hunter, and I'm going to assume it's because you feel a sense of duty and obligation towards the Empire... so like, you should go to the Colleges to serve the Empire better"
There are more eloquent ways to frame it, but I don't think it makes for a very compelling argument without a better understanding of Spätin's motives than what we have
Danger is also probably the wrong approach I think, because it's all info Spätin probably already has
If the danger of being a Witch was enough to drive her to go to the Colleges then she'd already be a Wizard
There is the "You'll have other people like you who will close ranks to protect you from persecution" angle, but I think that's better covered by Community
I think these three:
[X] Freedom
[X] Community
[X] Knowledge
Are my favored option for now, might revisit as the vote develops
I'm not sure how to feel about Wealth and Power at the moment