Just a clarification: I'm not the author of this AP, just a DM, but it seems that authors had similar ideas to you.
Thanks for the insight. The proposed scheme basically limits surge casting to 1 ritual/day "for free", and the following rituals will result in h.s. penalty, this may work. Zeitgeist has roughly "double XP rate" (actually, level ups just happen based on plot progression), and I don't want to slow that down, full lvl1-30 campaign takes a lot of our time even in this version.