Thoughts on comparing the gameplay of POE1 with the gameplay in the current EA stage of POE2.

POE1's Gameplay and Economy
Pre-season BD and Goals
During the pre-season stage when everyone is in the theorycrafting BD phase, various leveling BDs usually consider several requirements. First, it should be easy to build. This often means that most of the damage and survivability in the BD come from talents, ascendancies, skill gems, and low-rarity unique items. This indicates that during the leveling period, you won't get stuck due to the lack of core mechanic equipment, and in trading, your leveling BD has a low investment and high return.
Second, it should be able to clear T16 maps. T16 itself is not that special, but players need it because T16 is the high-yield area for most seasonal activities, such as Delve, the Garden, etc. Nobody would do Delve in T1 maps to earn currency. Of course, the value of T16 is not only in the seasonal rewards but also in the Atlas passive points, which often serve to enhance the seasonal activities. There are also ways to earn currency without doing seasonal activities, but as far as I know, most players still rely on seasonal activities to earn currency.
Third, we have to mention some activities in POE1 that don't rely on T16 to increase income, such as the Harbour Bridge, Delve, Essence, and beast-catching at specific map levels. These activities probably won't make you rich, but they are very important. They are the intermediate state between the campaign and the endgame, allowing novice, non-hardcore, and underpowered BD players to accumulate stable income when they can't keep up with the first tier, and they can slowly obtain equipment over time.
Crafting and Trading
In POE1, the materials for crafting are related to multiple activities. There are basic currencies that drop globally, Essence, Fossils, Beasts, the Garden, and special currencies dropped by bosses. Crafting, as the ultimate gameplay in POE1, drives a series of activity products. Players who do activities are the suppliers, and players who craft are the manufacturers. The behavior that completes this chain is trading.
One week after the launch of POE1, player behavior and the entire economic behavior are highly consistent. Supplier players disperse in different activities according to the characteristics and strength of their BDs to quickly produce materials, and manufacturer players use a large amount of currency in their hands to exchange for the materials of the suppliers until they produce "mirror-tier items". This is an industrialized idea: specialization (investing Atlas passives in a certain activity and specializing BDs) and division of labor (constantly farming a certain activity).
In the context of this industrialization, trading is the main line that connects all the divisions to complete the economic cycle of specialized material production, material trading and circulation, and crafting consumption and production.
Flaws in POE1's Economic System
The Sanctum. It is undeniable that the Sanctum has special unique item drops. But the drop rate of the Original Sin ring is too low, so the Sanctum must produce something of lower value to stimulate players' enthusiasm to play it. GGG's answer is to give basic currency, which conflicts with the currency dropped from mapping and is very difficult to balance. When the currency output of the seasonal activity is low, the output of the Sanctum will cause inflation. When the seasonal activity output is high, nobody will play the Sanctum.
T17. Looking at various T17 strategies, except for the boss map fragments, the output is nothing more than three types: currency, scarabs, and unique items. And these three are also the output of the basic mapping activity, which is the same problem as the above, conflicting and difficult to balance. And the low yield of T17 maps has led to the intensification of the gap between the rich and the poor in the entire economic system. This is a game, not reality. If the gap between the rich and the poor in the game is too large, players can simply quit the game.
POE2's Issues
I don't even know if crafting is the ultimate gameplay of this game. The EA test opened Essence, Treasure Chests, Shrines, Altars, Breaches, Mists, and Delve. Among them, the Altar produces semi-directed currency items, and Essence corresponds to affix-directed crafting. However, Breaches and Mists correspond to catalyst and anointment materials, which should be a numerical inflation system rather than a crafting system.
If crafting follows the division and integration model of POE1, there is no currency to anchor the trading process in POE2. This currency in POE1 was determined by the special crafting recipes on the crafting bench, from Exalted Orb to Divine Orb. This is also the reason why I think the current economic system has a currency ratio explosion event. Judging from the role of the Divine Orb, the output and consumption of the Divine Orb are probably unbalanced. Pricing in terms of the Divine Orb may lead to infinite inflation until the system collapses. I guess it may finally be priced in terms of Chaos Orb (C), because the special recipe of C removes the lowest tier affix and adds a new affix, which may become the anchor point of crafting.
There is no intermediate state between the campaign and the endgame. Besides the lack of low-level activities, the specialization process of high-level activities is not smooth enough. Take Breach as an example, to unlock the Breach talent, you need to defeat the Breach boss, and Breach fragments only drop in maps of at least tier T10+. This means that before obtaining Breach fragments, playing seasonal activities is a waste of time. The low-yield period in the middle can easily destroy the gaming experience of non-first-tier players.
There is no option to redo the crafting process, such as no reforging or remodelling. It's hard to evaluate whether this crafting process is good or bad for now, but it does increase the value of the equipment base, and the existing trading tools have no batch trading solution for bases.
The rarity is too high and needs to be adjusted. At least it should conform to the principle of low risk, low return, and high risk, high return. Instead of having hundreds of rarities and doing some low-risk, high-return things in low-level maps.