Well, I didn't buy this day 1, but I bought this this sale. While the gameplay is phenomenal I do have some complaints:
The combat mechanics is a bit more complex this time, you have the usual glory kills to get health, but there is a new attachment called a flame belcher that burns enemies causing them to drop armour and the chainsaw that causes enemies to drop ammo. You have to use all three of these to survive because ammo, health and armour are very rare compared to Doom 2016 so you have to constantly scavenge health, ammo and armour from enemies or from the arena you are fighting in. All of this while being attacked by demons from all angles, who are much more aggressive this time. Constantly moving is key to survival.
Every demon has a hard counter in weapon form. If you don't use the appropriate weapon when engaging a particular demon, you will just end up wasting a lot of ammo, which as I said earlier is scarce.
All of this contributes to very frantic combat, especially the boss fights.