The truth to be told, I'd rather have the charms again, not the gemstones. Gemstones were in Diablo 2, if there will be in DD, people will call it "rip-off".
The moment I saw charms I likened them to the
Diablo 2 gemstones. But a cosmetic change is good. I'd like to see more done with charms though. Let's take it to the next level!
Items-on-demand are interesting, I mean if you gather dragonscales and such... It was used in several games before so I wish Larian would make it more original... Like if you order a weapon, you can name it yourself(every good weapon need a name).
If the game has sets of armour, why can't you make your own set if you're such a hero? I believe that if you can collect a matching suit of armour (eg. Chain Boots, Chain Mail, Chain Gloves, Chain Leggings, Helm), and have it all enchanted in some way, then you should get an additional bonus for wearing all of that set. Each item would be called
The <armour piece> of <insert name here>, or better still, renamed by yourself. You could only do this once in the game, at a very special place, and the pre-requisits would be quite strict.