The username you choose needs to work for you not against you, so ideally it needs to be: – which one are you more likely to click on?
The second Frank sounds infinitely more interesting to me than the first one.
Are there any words/phrases/hobbies that stand out from the crowd that are representative of you?
For example, if you enjoy sewing, baking or painting you could come up with some examples as follows: If you create a memorable username that includes something you like doing, is unique, clear, positive and appeals to people not robots, you are already storming ahead of your competition.
Just a note on this: if you are stringing words together as above, do use capital letters as I have done so that it is easier to see what the words say when put together.
Lovesbakingbread, for example, is harder to read and is actually a bit off-putting, the exact opposite of what you’re aiming for.
Firstly, the most important thing is to make sure you’re using correct spelling and grammar (apart from the capital letter usage as outlined above).