Lovely posts Kirra, Shy and Ryv. These were a treat to read ^.^ And yes Ryv you don't have to post xD
I'm sorry I haven't been able to post I have been terribly sick for the past weeks, doctors are assuming its typhoid. Regardless I will have a post as soon as possible.
Just one additional information, in order to cast sigillum you must draw it where it can be drawn. Such as paper, or rock a stable source. Air is extremely unstable and even in stillness casting sigillum in air is a task that requires exceptional skill with the downfall of lowering precision. The problem here is, Reri has the wind in frenzy so that would be near impossible.
Addressing the problem around teleportation. Well there are two reasons why that would be difficult. First it will be considered dishonorable or cowardly to take it by teleporting. And if say an Asylum does try. Chrono's can often destabilize the alchemic energy around them for brief intervals by releasing high amounts of alchemic energy of their own. So if an Asylum does teleport, it would take a mele second for a Chrono to drop him/her mid teleport. Teleportation can often be sensed before it happens so that is another fact, the Chrono will know exactly when to ground you.
Trained Asylums who have some years under their belt can also perform this to a lesser extent against rogue alchemists. Say if a rogue alchemist is attempting to flee via teleportation, an Asylum can unleash his/her alchemic pressure to de-stabilize the alchemy for said rogue for few seconds. However this will be restricted to one or two rogues. Again this is considered an advanced art, often discovered and not taught.
Finally I want to know who wants to put their characters in peril and in return reap some amusing rewards. =P