the funny thing is that the first couple of posts actually describe the exact opposite. The crafting system is pretty simple once you understand it, cause after all, it's only really 2 items you need to craft a tier 2 weapon and that is: 3-4 kinds of the 6 basic materials (junk, metal parts, components alloys, wood and elec parts where applicable) and one special part (metal pipes for rifles, scopes for snipers, springs for smg's and shotguns, drum mag for everyting that has a drum mag, energy transformer for energy weapons). The game is designed that experienced players and platoons will have large supplies of the cheap components available while the special parts remain rare. The only thing you really need to care about is the special part and while at the start the different pipes and scopes can be confusing, it's possible to learn it with time.
As far as tiers go, there are only 3 tiers.
Tier 1 has the starting items, which are mostly useless once youre set up. It includes zip gun and pipe rifle, but goes up to ak-47 or even rpk, which is kind of a borderline tier 2 and I like to call them tier 1,5 as they are quite easy to obtain and do decent damage, but are clearly inferior to true tier 2. I didnt count but it's roughly 15% of all items that fit into this category, cocnerning weapons.
Then we have tier2. About 70-80% of all weapons are tier 2, which in turn leads to about 70-80 weapons if melee weapons and spears and explosives are counted. All tier 2 items are easy to get once you are set up. Past the levleling rush in teh first weeks, everyone will be able to always have a couple of tier 2 weapons available without even having to farm anything.
All tier 2s are supposed to be equally viable. Every weapon has a use, nothing is strictly better than another. Hoever, about half the tier 2's are considered rare, as they are not looted from (surface) patrols and are not spawned into the (surface) core containers. They have to be crafted, bought from merchants r found in dungeons. They often have a different playstyle comapred ot the common weapons n their class, but are not strictly better.
Then we have tier 3. Each weapon class has one tier 3. Right now only very few tier 3s are available, if at all. Each tier 3 has a different playstyle which soemtimes can differ quite alot from the tier 2's in its class. Tier 3's will mostly be craftable.
In conclusion, we have a levelled playfield and most "systems" in aop are explained with about 3 categories. Once you notice the categorization, understanding the whole system is simple.
edit: btw, I personally never played any other server than 2238 and only shortly looked at fo2. The only member of the devteam that actually played tla or requiem didnt join us until the game was already past alpha stage.