Making a review for this game is realy tough, but lets see where this goes.

1) Online feature
For the obvious downside of beeing dependent on Wolcen's servers you get .... basicaly nothing. All you can do is play with a friend. There is no lobby to chat with people or any form of group finding. Escentialy you are playing offline with the ability to invite somebody from your existing friend list.

2) Crafting
Right now the crafting system doesnt deserve that name. Half of the crafting materials do the same thing on legendary items so you only realy have 2 crafting methods. Removing and adding one random modifier based on the gems you inserted or keeping one modifier and rerolling the rest randomly.

3) Itemization
Uhm yeah where to start....
Highest possible itemlevel is 189. Every item scaels its mods through the item level which means that untill you hit the last level in your missions you will find the exact same items over and over again just with slightly higher stats. So in esence it is an infinit scaling system. This means that every 10 item levels or so any gear you found prior to that becomes meaningless. Unless you want to gear a second low level char there is absolutly no point in keeping any item.
Unique items do offer some affixes that cant spawn on other items and some of them do enable different play styles, so all in all they are designed ok. Just that they suffer from the same fate as normal items, meaning you will replace them frequently with non-uniques while progressing just because of the item level scaling.

4) Endgame
The endgame consists of a managment mini game, running expeditions (essentialy rifts for all the D3 players out there), unique areas through maps and missions.
I have run exactly 1 mission. They dont scale and are meant for anyone that cant beat the first stage of expeditions. Once you can do that you will never do them again.
Expeditions are are semi-random areas in which you will need to kill enough monsters (no timer) so that the boss spawns. Once you kill that boss you can either go back into town or go deeper. Every time you go deeper you increase the monster level by one and through that the item level. Every 3 Stages you get a checkpoint that allowes you to start your expedition at that monster level.
At level 189 (highest possible) the boss will have 160-190 million HP.... Making a build that can clear these levels fast is hard, making a build that can not be killed is not. Hint : Shieldblock efficiency+resi+leech - throw in the autocannon turret and you have a build that cant die and just waits around for a bit untill everything dies ;)
With every player level up ALL stats loose efficiency. That means that while leveling up (and all the way to 90 takes a loooong time) you never feel like you are increasing your power but rather you are just trying to stay at the same powerlevel.
If you take away any scaling items issues etc and look just at the raw gameplay of expeditions I actualy quite liked them. But overall they are subpar. If you liked D3's rifts you will feel right at home here, but if you disliked them - well better look for a different game.

5)Your demonic transformation.
Its a joke. Use it the few times the story requires you to do so, then unbind that key. Problem is, that it doesnt scale the same way you skills do. So as soon as you are done with the story it does 0 damage compared to your regular attacks and therefore looses all meaning.

6) City managment mini game.
This system does have its potential but right now its borderline useless. Getting your static buffs from it is right now its main purpose. You can use it to increase your crafting reagents ability to also work on legendarys and you can get more of them. Oh and you can upgrade items through it.
You could also get items, gold and the primordial stuff through it. Items are LOWER itemlevel of what you are currently farming - so useless. The chance for actualy getting what you want in the other missions is so low that you are better of not wasting your resources.

7) Bugs, crashes etc
Surprisingly I had very few issues running missions. Any other are of the game is riddled with them. From quest not working, falling through the world, game crashes, system crashes, animations not triggering, the Uber boss not dropping any loot etc pp

Verdict:
Just the game would get a 5/10 from me. The gameplay itself is fun but suffers from item/attribute scaling. Combine that with the current state of bugs and this goes down to a 2/10.
Either wait untill the bugs are fixed or just play Diablo 3 - the endgame is essentialy the same but D3 has actual mulltiplayer.

*Edit
Ok game just lost me. Turned my Ilvl 189 Item that I spend hours on crafting into an Ilvl 77 Item ... RIP GG and Goodby