No, you should not remove any tables from Concrete5. They are there for a reason and unless you want something to break in the future (or possibly immediately) they all need to remain intact.

The only exception to this rule is if you installed a plugin which added it's own tables, and it did not remove them if you uninstalled it.

Edit: The reason for the numerous tables in Concrete5 is because of it's ability to be dynamic/adaptable without expanding the number of database tables (in many cases) as well as the number of features that Concrete5 has.

Interesting...so I guess I just need to see what was left behind....ok thanks...

As @exchangecore notes, you shouldn't remove tables. However, a fair number of tables can get bloated and can usually be reduced in size.

Page statistics is one of the worst tables on a busy site, so unless you need them, turn off page statistics in the dashboard.

There is a core job to remove old page versions for 3 pages at a time. You can go to the dashboard jobs page and just keep running it until it reports nothing left to remove.

There is also my Extreme Clean addon (free) that scours old versions and trims logs thoroughly - but always backup first, just in case you clean a bit too thoroughly.

Someday it might be nice if Concrete5 allowed some sort of "site" concept in the database to allow you to have numerous sites running on the same database. This could impact performance, and wouldn't save you any space (or not much), but it might allow you to have a multisite setup that all utilize one database and one set of c5 core files.

Something to wish for I guess...

If such a namespace prefix was going to be incorporated into the core, I suspect 5.7 would be the last chance to incorporate such a change for many years.