present perfect / simple past sentence

Hello,

What do you think about this sentence: Should it be in the present perfect or simple past?

1) Ever since he has become a doctor, he just came straight home and took care of his family.

Should I change the above sentence into one below? Are the sentences below correct grammaticaly?

a) Ever since he became a doctor, he has come straight home and taken care of his family.

b) Ever since he has become a doctor, he has come straight home and taken care of his family.

c) He has come straight home and taken care of his family ever since he became a doctor.

d) He became a doctor. Ever since, he has come straight home and taken care of his family.

we use present perfect for something which has started in the past and its results are obvious till now. Therefore I'd say:
Ever since he became a doctor, he goes straight home and takes care of his family.
I hope it's right.

a,c & d are OK. Becoming a doctor is finished, so should be in the past tense. ;-)