You will no longer be suffered by iOS 6 Hiragino fonts.

UILabel+AKiOS6Compatibility.m

- (NSString *)text6Compatible
{
    return self.text;
}

- (void)setText6Compatible:(NSString *)text6Compatible
{
    self.text = text6Compatible;
    
    if (SYSTEM_VERSION_GREATER_THAN_OR_EQUAL_TO(7)) {
        return;
    }
    
    // フォントがヒラギノだった場合のみ盛大にぶっ壊れるので、ヒラギノかどうかで判定する
    // ヒラギノ (Hiragino Kaku Gothic, Hiragino Mincho) の時だけ補正をかける
    if ([self.font.familyName hasPrefix:@"Hiragino"] && self.text.length > 0) {
        NSMutableAttributedString *attributedString = [[NSMutableAttributedString alloc] initWithAttributedString:self.attributedText];
        NSMutableParagraphStyle *style = [[attributedString attribute:NSParagraphStyleAttributeName atIndex:0 effectiveRange:NULL] mutableCopy];
        style.maximumLineHeight = self.font.pointSize;
        style.minimumLineHeight = self.font.pointSize;
        [attributedString setAttributes:@{NSParagraphStyleAttributeName: style} range:NSMakeRange(0, attributedString.length)];
        self.attributedText = attributedString;
    }
}