I agree with almost everything you wrote. I really wish Larian had marked empty vases/jars/corpses/etc. as empty or simply made them unclickable. For now, the game only differentiate between "have been interacted" and "have not been interacted".
Except about achievements:
Some achievements make NO common sense. I was forced to be evil and screw over everyone to earn my last achievement (which was easy but I didn’t want to), but saving “everyone” in the Iron Throne prison (which is difficult) isn’t worth an achievement???
I don't think they are picked solely based on how hard. Some are picked just for a record, including all the ones you get simply by completing certain parts of the game or the whole game in certain ways. Some of them are more for fun than for a challenge, such as the one for saving a service dog and the one for repeatedly helping an otherwise insignificant goblin survive. Some are purely for fun, like the one for killing some enemies while drunk. Only a small number of achievements represent a reward for taking on a challenge: for example, the Kapow achievement for killing a dragon airborne.
Regarding the Iron Throne rescue:
I guess this can only be hard when players are here for the very first time. When I stumbled here for the first time after refusing to heed the warning, I kept rotating my camera for (literally) an hour trying to figure out a way to do that. I successfully rescued all 15 prisoners (as far as I know, that's the max possible number of them) - even against the harassment of a naughty devil - even after I made several silly mistakes (in hindsight).
This rescue mission is more like a puzzle - once you have solved it, you have solved it forever. For me, I learned how to rely on Karlach for rescuing 9 of the 15 prisoners in an optimal way. I can repeat that indefinitely. 3 of the prisoners need no/little help, Only up 2 more characters are need for the remaining 3 prisoners, including the duke. Given a party of just 3 handpicked companions (or just 2 companions + summons), I can almost guarantee the success of the rescue - at least against the current 5-turn timer on Tactician mode.
It's fun. It's a good challenge in a most intriguing and enjoyable way. I wouldn't object to having an achievement for rescuing all 15 prisoners. My only concern would be: it may accidentally reveal spoilers - how would you know how many prisoners would be down there? In fact, how would you in advance that you would have to rescue them - as well as yourselves - once you decide to dock?
