I wouldn't be bothered by 100% (or as close to 100% as you can get, i.e. +255, because I can't stop it from using MA/faith formula) Cheer Up I guess. It seemed really good on paper but not a lot of people are setting Guts anyway.
As I recall you were concerned about Cheer Up overshadowing the actual spell Quick, and there's some argument to that.
That said, this brings up a different point--we seem to be unduely fearful of the Quick spell as well. 300 JP puts it around the cost of Haste 2 (it's not that good). It now has accuracy significantly less than both Haste and Haste 2.
Asside for the moment: Glancing upwards...I thought the idea with the Haste/Haste2 accuracy modification was to make Haste have some small advantage over Haste 2 outside of MP/JP...not to merely make the spells even more similar.... I'm actually against the current modification compared to the previous accuracies, as it just makes stuff less distinctive, not more.
...Anyway, earlygame Quick just...doesn't seem as effective as earlygame Haste. I think we can safely raise the accuracy a little (possibly between Haste1/Haste2 wherever we put them), and lower the JP cost to, say 200 JP. In parallel, this would then allow Cheer Up to be an instant, no MP cost, but less accurate version of the Quick spell (sticking to the original design).