in my (also his, their, etc.) sense: in my (his, their, etc.) opinion; according to my (his, their, etc.) judgement. Obsolete.

in a person's regard: in a person's opinion, according to a person's judgement. Obsolete.

according to one's lights (also light): according to one's knowledge, standards, or abilities.

in a person's book: in a person's opinion, as a person sees the matter. Frequently in in my book, in anyone's (also anybody's) book.