Thank you for your feedback!

As for the PW length, there is no particular reason why it was set to 20. I just figured it is enough for a random password. However if one likes to have a peculiar sentence as password for example (which is quite secure) it is not enough. I set the PW length to 30 now.

As for the Timezones:
I think the list is the best and simplest approach, also how the timezone is stored in the database. It's a bit overwhelming at first. But unless you do travel around a lot it is a setting that must be only done once and never again. Also it is ordered by continent which should help.

UPDATE:
I have added timezone abbreviations to each city now, hope this helps. :)