After finishing the first chapter and starting the second one, it's..... uhmhnhhmmmm.
Tons of people in the thread have already indentified the basic problems of the game, but I'll add my points:
+ The graphic style is bad but serviceable in motion. I agree that such a style made possible a great variety of enemies, but the great variety means nothing if they aren't employed skillfully and if they don't feel different. Succubus may be different from Ice Psych Man but the only real difference is that the Succubus takes one magnum shot and the Ice Psych Man two-three. Same with small melee enemies or others. Still have to see the other chapters though, things may improve. Biggers enemies with more creative routines show promise, at least.
+ The level design is bad. At least, first chapter. It plays like some random SLIGE map or a 14 year's old first .wad. It's boring, repetitive and visually indistinct. The first fight that gave me "hey, this one is not dying to random fire!" was on level nine or ten. If I wasn't curious about the game, it would have been an istant drop. The first boss is legit hilarious, 'cause I died the first time trying to check the attack patterns an' shit. Second time I took out SMG, didn't even move, dumped 200 rounds on him and finished him with the double shotgun, in roughly 30 secs and with almost no damage. Iffy design.
+ Weapons variety is nice. Weapon unlock system is weird but good enough. Magic system is useless and could be cut with little loss.
The level design steadily improves though in the Antarctica levels, at least its simply acceptable instead of actively painful. It's a commercial game clearly inferior to the vast majority of Doom's wads, but it shows an inkling of promise, that I'll admit. Let's see how long if it improves further (and this begs the question, why giving you shit levels at the start?)
EDIT: Forgot. Also take the goddamn guy WHO DID THE GODDAMN MUSIC TAKE HIM IN THE FORESTS AND PUT A 9MM IN HIS BRAIN. I am joking, but in a shooter I need to feel pumped, not being reminded of SS1's elevator music with a meaningless random soundtrack of digital beeping.