Hi Alen,
Thanks for the logs, yes it appears that the problem source is coming from the database as it might be not in stable state (due to a crash or not able to close properly).
You can follow this community post where there seems to be a solution i.e. to clone the current database and then replace it with the existing one as it may solve the issue.
Regarding the other part of your question, yes can use other database flavors e.g. MariaDB/MySQL or Postgres as it is totally up to you.
For e.g. if you think you are more familiar with MySQL then you can use it. The only things come to play later if your database grows in size, then may have some performance issues and atleast I know for MySQL there are several performance analyzer tools e.g. MySQLTuner to assist user with some suggestions.