Stats have to be adjusted because our Compra got it's stats adjusted, (I believe) all monsters in Tarian have got their stats adjusted, and with the current amount of +20 or higher weapons, the new monsters need to have their stats adjusted if Aeria does not want those monsters to be 3 hit (and to keep the armour from being common).
About the facts/conspiracy theories/assumptions, you are correct. Aeria has sold power (Master Stones) to the players, so now new content which was designed for the game it was supposed to be (no Master Stones) has to be adjusted to those Master Stones.
Making former free to play content more pay to play.
A direction in game "development" that fits well into already implemented things like virtually useless supporters (weaker than pots), stealing of skills (and replacing them with items) which is likely to finally get this version of LC down like the korean one.
The poor argument that something should not be common is contradicted everytime when monsters can not be killed without the "uncommon" things, thus making the "uncommon" things needed in such amounts that they become common anyway.
This sort of game "design" can well lead to frustration for all players not willing to pay a cars prize for "uncommon" pixels, so quitters will reduce the amount needed.
If that is all the designers are capable of, no wonder their version did not stay online.
After 4 years they still not understood its useless to balance everything for some overequipped solo classes then let all players and all classes try to meet standards set this way.
Back to topic: dont expect anything special. The exp eagle, some monsters (some more of the land of copyandpastiya), some more disbalancing, the usual amount of bugs.
Oh and those awesome (?) pieces of equip.
I do not believe i forgot anything important in this list.