Lansweeper Classic (I hate the 'Classic' addition to the name) is indeed a great tool for real Sysadmins. It gives you 100% control over all your data. Anything you see on the asset page, you can report on. Data resides on your own SQL DB, so you can query whatever you want, or add additional data/tables (eg. financial data, location data, 3rd party app data, ...) and with a few blink of the eyes you have a new, one of a kind report.
Data can be easily exported to a (local) file or emailed (haven't found this feature yet in Cloud) on a daily, weekly, ... basis.
Registry key and file scanning seem to be disappeared in Cloud, this is a very important feature for us.
Cloud version reacts slower than the 'Classic' version.
Classic custom fields are not synced with Cloud custom fields. We have loads of custom fields, and all our custom reports (>50) rely on them.
In Lansweeper Classic, almost every attribute is clickable and brings you to an overview page of assets sharing the same attribute.
The 'Mass Edit' function is very handy in 'Classic'. Not to be confused with the 'Bulk Edit' function.
The "Configuration History" and "Changes by Type" reports are missing in Cloud.
And I think I can go on for a while...