1) Achievments must be rebalanced. So many comments about that already. Playtime highest achieve can't be more, than 1 month (and it still incredible long). Clicks achieves may be 300k-500k max. Date/gifts maybe 15k-30k.
2)What actually multiplayer gives? Need explanation.
3)Soft-reset system must involve some repeteable game-rewards. It may be diamonds from girls (maybe only from 4+ stage) or extra-multiplayer.
4)Time blocks from diamonds don't save? WTF? I wanna my diamonds or blocks back. And fix it.
5)Some way to speed-up hobbies and works would be nice. Maybe not clicking. Minigames 0_o ... And maybe way to put extra-time blocks in something to make it faster. Maybe x2 blocks for x1.75 speed.
Is there any profit from restarts? I did three, and looks like it only made game harder with no extra features. It's bad.
And clone equipment is very boring, this game can be five times better only if you add random items.
I think explore have feature "upgrade to be worse" just like craft, yes? Can't you tell what affects gem chances by explore, maybe which stat needed to be lvl down to get gems oftener.
To me it is/was logical. You start making higher level equip, you aren't practiced at it, level is generally higher, rarity is genuinely lower. As you get better at making that level of equipment, the quality improves and you get higher rarity equipment. Eventually you get high enough and go to next level. Its not really a cap, your rarity will go up again once you raise your stats a bit, but there is a formula which takes your stats and choose how many levels/ and how much rarity goes into each piece. It's basically the same as a dice roll. You get an extra dice roll as your stats go up.
Silvadel is right. You must check all your math, somewhere must be a reason why on pretty high crafting level player loose chance to do blue or higher. First time, when I wrote that, it was the same. I deleted one worker than - and got ability to craft again.
You dont have to take off a worker, but a small stat change can help to get you out of crafting slumps. Often removing changing a single piece of equipment will do it. When you are super high level, your stats change much more slowly, so you can end up getting stuck in slow spots for longer times. Try swapping a single piece of equipment or two, and you will most likely end up with lower level equipment, but higher rarity
Another two comments:
Random Upgrade lvl 7 gives me only 3 upgrades.
Construction cap and dungeon levels upgrades gives far bigger, than need bonus. You need just few of them for even very long play. Nerf them.
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Shop sell the basic items, usually without slot or with less than the version provided from monsters loot