I have a long draw with moderate poundage (32", 70#) so I get limited by availability due to length and spine. Might want to start there if you have similar issues. After that, I looked at gpi and unfortunately most were ~11, but found the Victory RIP XV's that have 7gpi 300-spine. That...
I'm admittedly not great - usually off about +/- up to 20%! haha Been working on it though, until then I keep my rangefinder close at hand...
Somedays I'll be pretty dead-on though, so maybe like @Blockcarver said, could be conditions.
I have some Eizniz off Amazon that I'm pretty sure are a knock-off but they've been the best I've tried! I have Meriwool, Duluth (non-merino), and SmartWool. The Smartwool are ok, the Meriwool seem to just be to flat all-around, they bunched up all over when hiking (basically moving legs more...
I've got a Travelchair Joey I got off Amazon (other places have them) for $60 (now $45), and it's about 2.3 lbs but really sturdy. I looked at the Helinox One and others but wanted a higher seat height (I'm 6'4"), and many were like 9-12" off the ground. Big Agnes was mentioned earlier too...
Lowa Tibet's here too - though the factory insole sucked for me so I switched our for Superfeet Green's. After that they were AMAZING! I actually strained / lightly sprained my ankle a little over one week before my CO hunt last year, and the boots had great support to where I barely noticed...