1) That's really subjective opinion, its also wrong one. Weapon parts was a tedious grind of both perks AND parts, current solution provides ACTUAL customization that didn't existed before, I'd take weapon mods over parts anyday. Guns also aren't supposed to be murdermashines, it all depends on the shooter, I can guarantee you that 100 year old pistol will kill you just as fine as top quality one made today. Also, so what if you found all these guns? You do not have skills to use them to the fullest nor you have the ammo to use them for more then couple of Zs or POIs.
Fairly sure that a 100 year old not maintained gun is going to kill you faster then the zombies.
But in all fairness, the mods are interesting. But removing the gun parts was unneeded. Now people find pristine working condition guns on day one if they get lucky.
A better system might have been weapon mods plus full gun BUT with the weapon parts as before. You find a gun ... the bold may be broken, the trigger is ok, the barrel is toast. You can disassemble the gun at home into parts and combine it with other parts. It keeps the old parts system but remove the unrealistic element of finding mostly gun parts in pre A17. Mod can be used to enhance the weapon.
Sounds like a better system where a getting a working weapon is actually a bigger deal, then now in a17.
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And to address the OP his post: There really was no need to level gate iron tools etc, If somebody wanted to spend all there points into int, let them. Its already a lot of points to spend. TFPs complained about spam crafting but keeping people locked outside specific skills by levels in combination with points, is just annoying. They made a big deal out of the skill system but in a lot of discussions kind of ignored the fact that level gates are a thing again!
The Zombie are XP goldmines is also overdone. I am sure somebody will do a Excel on it but now you zombie craft for xps all the time. Forcing people who liked the building survival mechanics, into constant zombie hunters. It really cheapens the game its core technology.
Why even have a voxel game? Why deal with the performance hits... Plenty of games that run on Unity that have building that is less taxing on the system that are heavily into PvE hunting. Where building is more side effect.
Its a shame... I do not deny the hard work that has gone into a17 but i found a lot of my prejudices came true about the direction a17 has taken. Its now more a horror survival dungeon crawler then before. Now we also know the lack of new late game content become its not needed in TFP there eyes because of the massive xp grind now on the start to mid game level.
It explains the lack of real progress on the electricity system and other concepts. I feel it will be up to the mods AGAIN to fix up 7D2D. Some people will love the new changes but #notmy7d2d ...