Using a mix of lower and upper case letter(s) along with number(s) and special character(s) is strongly recommended.
Please note, starting with a capital letter and/or ending with a "!" is a very common pattern and will reflect in your score if you do so.
A password scoring 55 is considered medium while a strong one starts with a score of 75.
A score of 100+ is recommended if you want a very strong password for the years to come. Password cracking technology doubles in speed about every 2 years.