Greetings Nuitari! Your memory serves you just fine!!! That are exactly the spells I had in mind.
I'm afraid invokers will use it primarily to double their firepower (Just imagine two vaporchains in a single round.
That is easy.
Make it rarely useable. Even when you cast it you can cast it again only after a while (example - as a ranger I call on animals and get that ability again only after a large period of time).
Mages are in fact pretty strong when used with skill. Giving them the ability to autorecall in low health, or the likes, is something I cannot agree on.
The life story of every mage is: extremly weak at low levels - extremly powerful at high levels. And, of course, terminal lack of health, and lack of proper armor. In every fantasy game I ever played none character can match a
prepared wizard in power and ability to wreak havoc.
But the word that catches the attention is prepared. And thief or assassin can make a short work of any wizard. And every fighter with, incredible-amount-of-attacks per round and unspeakable damage (not to mention heretics in this case) can also do the same.
Spelltriger or contingecy should help in that case, making it more probable for a wizard to survive. And a downfall would be to activate ONLY on prearranged conditions. Not ALL of them. So you can use only if you are backstabbed, only when strangled, only when assasinated .... and so on.
Whatever you decide I still like the idea.
P.S. In the end I still want to remind you that I think that all of you immortals do a great job of maintaing Solace !!!