So I was thinking about making a were beast wizard. Gameplay wise my character would work as a blaster and support but when necessary he goes all Bear or wolf and help the barbarian or fighter. Also I wouldn't let my character do magic in his full animal form and maybe not even his were form.

As for his Backstory he was born a werebear (I like bears and they have a good alignment) and early in his life he attacked a friend of his. Never forgave himself and devoted his life to studying magic in hopes to figure out a way to undo his lycanthropy. But thing is he was also attacked by another werebeast whether it be wereboar or a bunch of wererats but the effect is the same. He has many forms that he turns into but he is a nightmare during the full moon constantly shifting uncontrollably and being prey to his own basic instincts.

The reason why I say this is two fold. 1 I really like polymorph and being able to have a few forms but no spell slots for them is great. And 2. It gives a weakness that if it's the full moon he can be the threat

My main question is how as a DM react to this proposal and try to balance it and as a party goer react to learning a member of the party is a multi animal lycanthrope.

Also how many forms would be to many? Like I fell like 3 sets is pushing it but whats your opinions? I mainly just want to cheat wildshape into my wizard character with a few drawbacks. So how'd you game balance this and how do you like the idea?

Also the forms I'm thinking he was born a werebear, gained werewolf or wereboar (a second strong form), and a wererat or a wereraven (a small mobile form).