I like it!
Definitely makes summoning more interesting.
A seperate “house rule” thread might be best. Both to avoid confusion with the standard rules and it would give us a chance to bring together all of the fan made rules posted in various other threads.
An other thing I think would be cool for Crom is a creature thread where people could post their monsters / henchmen / villains …
Maybe you could make them a sticky in the fantasy forum?
If you like small scale skirmish, check out http://planetares6.blogspot.be/?m=0