Hello Banister,

Ubuntu works measurablely slower then the basic debian, (possibly it has more modules loaded in the kernel and default "on" system services . ) So unless explitly needed better to stick to debian itself. Once you start with ubuntu it may be painfull to revert to basic debian.

I myself call ubuntu "windows of linux ecosystem" :)

MariaDB is ok for smaller installations and even bigger, but it is a different path and diverted from mysql, if you are experienced tweaking it, it is ok. I used it for a long time and still using as my main UNA database without any problems. Maria also works a little faster with correct settings as it is more optimised.

You may have transfer difficulties in between hostings if one uses maria and the other mysql. You can not copy the lib/.. files and sometimes mysqldump may not give the exact same results in between them. But unless you use the same DB there is no problem.