The DM is abit strict in what he allows. He generally only wants phb stuff because thats what he knows. He did allow 1 player to play a artificer and ive asked him if the feats from Tasha's are oke but he hasent gotten back to me yet. Its worthwhile to point out though that the DM took over beeing the story telling for me so I can recover from my operation at my own pace. If I have to sit a session out or something that way doesent stop the group from having a dnd night. So I dont hold the restrictions against the DM. It can be.... challenging to play with source books you dont know and half of the players at least have a bit of a power-gamer mentality.
Taking shield mastery kinda goes against the heavily armoured feat because the idea was to be a heavily armoured wizard. And a shield doesent have the same charm as wearing full plate
