On which place in the top list of linux distros you would put Lubuntu

For my purposes and uses, I'd put it in maybe 6th or 7th. Since its primary goal seems to be being a lightweight version of Ubuntu, I'd say it very much accomplishes that. I personally prefer more visually pleasing distros, though. I've enjoyed bringing some old systems back to life with Lubuntu that otherwise wouldn't be worth trying to use in the past, and most other lightweight distros I tried were very stripped down in ways Lubuntu was not. I tend to prefer Manjaro and full-on Ubuntu over variants of Ubuntu, but it serves its purpose well enough.