Sorry that I did not read all the info,it is really confusing
I had those glitch before,I had 2 stack of Baked Yam(2*99),one stack sold in normal price(300++),but another sold only 50 each!I experience this twice,one Baked Yam,one Roast Eggplant.
I notice that whenever I have more that 2 full stacks of cooked crops,one of them will become very low price.
(from my exp,this glitch affects only cooked crops,i did not have any problem with 2 stacks of original crops,or seeds.That's from my experiece,though...)
I am in second year Summer,somehow,sometime,my eggs disappear,5 eggs left only 1 in the nests when I check in the morning,I am not sure whether is this the same glitch.
Then,my cat nowadays was like going crazy...It cant take care of my 5 chickens properly even though it has 8heart and 8 stars.I just found one chicken out in the rain,with a lot of stress,should have stayed overnight outside....
And for the lvl/rank will affect the products or not,I want to know about that answer too.I notice that at the beginning of game,1st year,I cook one 5star Sculpin,and I will get 4.5 star or 4star Shashimi,however in 2nd year,I get a 5star Shashimi just by cooking a sculpin without addition.