Runes (and Glyphs, Seals) have to be 'read' to be activated. I don't really see those working instantaneously. BattleRunes clearly allow instant spells - but at very high cost so it would seem that 'regular runes' would not be suitable for instant spells.
I think you have to go with Charged Items, Single Use Items and Daily Items for 'instant' type spells. Those are just 'activated' by the attuned wielder and that would seem to allow instantaneous spells (we certainly do it that way in my campaign). Items being enchanted rings, wands, necklaces, bracers, coins, cards (in a nod to Zelazny), etc. The only problem there is Attunement since even the Single Use Items require prior Attunement . This not a big deal for magic using characters but slightly problematic for the non-magic users.
Of course, this is predicated on the Thaumaturge spending DPs on Arcane Circle [tying into the multi-profession thread] to get access to Bladeturn and Deflections. Typically, during down times, the Thaumaturge cooks up a batch of utility Single Use Items. So with a batch of Single Use "Long Door Cards", "Minor Healing Coins", the non-magic users will likely get lucky and get attuned to some of them.
My campaign is highly magic centered and so the fighter/thieves are actually Shadowblades, Rangers and Warrior Mages and so the Attunement issue is not usually a problem.
Robin