Is this password strength consideration makes sense?

I have a logic that shows password strength meter in javascript. A password is considered strong when the following criteria is met:

• 8 characters long
• At least one special character
• Mix of numbers and letters

At the moment, this password combinations pass the strength meter:

• @@@@@@@@@@@@@@@@@@@@@@@ (Has no numbers or letters)

• AbracadabraAbracadabraAbr (Letters only)

• 1234500000000000000000000000000000000000 (All numbers)

Does it makes sense to disregard the length in those cases and set it as weak a password?