My guess is to why we havent got much patches these couple of months is because they(the devs) lack the necessary funds to keep making more updates to the game.
Even with IAP ingame like character slot, premium stash and skins which are available for anyone to purchase to support the game, its not mandatory and clearly isnt enough for the devs to warrant the idea of using their time and resources for a game that doesnt make much money for them.
I could see DQ one day incorporate a Quarterly Battle Pass a very popular microtransactions within some trending games like Dota2, Pubg and MTG Arena.
An example would be that anyone can evenly access the rewards like gold, chest, dust, pets and even skins but the the BP buyers would get the rewards faster and/or have more exclusive stuffs to get like premium versions of skin(prestige skins like in LoL).
If any devs can read this, Hey! Im willing to pay for this to support you guys!(please be fair with the pricing).
Thanks for the read again! 