cheer, frame, habit, humor, inclination, mode, spirit

angle, attitude, mind-set, outlook, perspective, slant, standpoint, viewpoint

emotion, feeling, heart, passion, sentiment, spirit

strain

belief, conviction, judgment (or judgement), mind, notion, opinion, persuasion, view

expression, tone, vein

character, identity, individuality, makeup, mettle, personality, selfhood, self-identity, setup

responsiveness, sensibility, sensitiveness, sensitivity