The last time I tried to play the game it was 2 patches before release and I couldn't play with that system. How is it not valid critique if I can't play with it. If it makes my gameplay experience so bad that I can't even play for more than a few minutes ad quit in disgust? Bear in mind that before said system was put in place I would play the whole content available of the game and sing nothing but praises to the game!
Thing is, your critique is essentially bad first impressions.
It is very valid as first impressions, but only as such.
Since you did not experience decent amount of play time with it, you can not do proper deep critique of it. Only "theory crafting", and what you think game would feel when playing with such system when getting deeper into game, despite not playing nor experiencing it yourself.
Thus, your feedback is less valuable as such.
As for the oddity system. I personally do not like it because it does not fits my playstyle. I don't really want to have to go around finding the scatered oddities to level up. I prefer the classic system. Do quests, kill things especially since the way I like to play the game is kill everything... I did not say it was a bad system, I just don't like it, it doesn't suits my playstyle but as long as it's an option over the normal XP system then I won't complain about it, but I certainly will not use it.
Oddity system is great for exploring, essentially the thing you think is lacking due to the loot/trading system.
And just to know, you still do get XP for the quests.
Also, I do not really see the need for XP for killing enemies.
For human enemies, their loot as well as passage you clear out, is reward on its own. Yes, loot. Just because metal armors and hammers are difficult to pawn does not mean there is no more then enough other valuable loot that weights less, or useful items to keep. Firearms are easy to pawn (value of 1000 per kilo) or stash and pawn later.
For monster enemies, reward is crating components. Also, due to monster respawning, which is necessary for crafting system to work correctly, oddity system is better, since it does prevent grinding for XP which is ugly and outdated RPG mechanic.
Merchants should buy everything so long as they have cash.
Why should they? For player convenience? Merchants should follow their own interests. And that means the need to keep their buying power, instead getting everything from first adventurer that arrived that day, so that when there is something really interesting that they have cash to buy it.
Second, carry weights. Realistic or not, all that it acomplishes is force the players to stop doign whatever they are doing to go sell stuff and thus break immersion (this assuming the merchants would actually buy everything).
No. The stashes are there for the reason. If you can not carry something, stash it nearby, or just leave it if it is not worth carrying. Return for it later when you finish your adventure, if it is valuable enough to be bothered.
Also, selling immediately is not mandatory. Keep items and stash them near compatible merchants to sell later when they get buying power back.
Also, post Junkyard, players should be swimming in money, so there is not even requirement to sell most of the stuff you accumulate in stashes, in order to buy other stuff. The only exception being cosmetic house upgrades in Core City or Super Steel Bars from Foundry for advanced late game crating. But at that point, there should be more then enough merchants to pawn most of the valuable stuff.
^This still does not mean that exploring and gaining loot is not rewarding. It is, because for every several items that are only worth selling, there will be something else that will benefit you directly to keep. Either being crafting component, ammo, or weapon/armor that is better then you use, or an oddity item.