So, current thoughts on this, is that this is pretty awesome.
After getting bloody Storm Dash and getting THAT out of the way, MOST of my time in-game has been spent exploring; been awhile since I've been able to say that!
I think you guys have hit the sweet spot for the frequency of the arcane items appearing in stashes and such; I'll probably never have too many, but at the same time there arent too few of them. Making spells outta those will take some work, but not so much as to be annoying. Exploring surface areas and caves for secret missions to get scrolls is also important, so I find myself exploring all 3 area types. Very, very nice.
That being said, I havent gotten to compare common and uncommon spells; when I tried to craft an uncommon one just now, the game..... utterly ignored me. Clicking "craft uncommon gem" did absolutely nothing. To see if the rest of the menu worked, I intelligently blew it on the common version instead (that was smart). That did though at least let me craft it. I tried to craft uncommon Fireball, specifically, to compare it to the common version I already had.
I have some uncommon orbs, so I'm not sure what happened there....
Still, right now, this is SO much better and more enjoyable than it was before.
Oh, and the bit about the enemies being in their tier-5 mode.... yeah, dont change that. It's making the combat pretty awesome. I suddenly realized, I almost never saw enemies at that tier before, because upon actually hitting tier 5 on a continent, it was usually time to go attack the overlord pretty much right away. So, didn't run into that many monsters on the way.