Thanks for your thoughts. I think context is everything and regarding my character, I'm only midway towards completionist and only play R1 to R4 as an average player as I slowly work my way through Racial lives. Because of the difficulty I play at, I think GCS is a far more viable option as opposed to you completionist monsters who like to solo R7 to R10 content.
in all honesty I do not have the expectations to solo r7s when I try new stuff. definititely not while leveling.
r2 is isualy the solo leveling place, r4 if it goes smooth. at cap I aim to be usefull in r10s becouse that is where a lot of my friends play at.
the difference in dc requirements from evening star to ravenloft and up has always been a big hurdle to overcome. But generaly it has been relatively easy to get dc's high enough for epic leveling if I max the required stat, feats and craft the usual insightful bonuses and such.
the exceptions being trip & stunning blow dc's wich I used some year ago and caused me to have a meltdown and take a break.
I dont know if it was fixed but the dc's just didnt work.
I think you will atleast be able to use gcs on most melees and if you go for glacial wrath it will work on most casters.
I'm using falconry now and that is also pretty sweet. the aoe blind bird attack doesnt open for sneak attack wich is a bit annoying, but it is still very good to use in a full room defensively.
The lvl 18 core in ninjaspy has suprised me with it's usefullness while leveling. it's an on demand tank that diversion dummy. anything that can be intimidated goes for it and it lasts a while.