You still have the option to play on the newly released legacy server, where Amii Monument still functions the same way it did previously. The team has also buffed a number of T3 cards already with more improvements to the T3 experience in the working.
Not sure what you are talking about with the nonexisting economy. There are currently over 4500 auctions listed in the auction house with most prices being relatively stable after the team introduced features like reforging and Rebirth boosters. Tou also have other options for trading, such as the ingame trade chat and the trade channel on the official Discord. In my experience as a player the only thing, which can require some time to find good offers for are rare promos, such as Ravenheart.
The team has already introduced around 25 new cards to the game and did major buffs and reworks to countless others. Meanwhile, there are very few deck archetypes and strategies, which have been severely nerfed. I would really suggest you check out all the options you have for deckbuilding right now and compare them to what is possible on the legacy server before coming to such a conclusion.