Based on your interest in being an ethical person, it seems like this situation could work out very well. It’s totally possible to get the place set up so that you rent out a nice, very livable space for a tenant that is less expensive and/or nicer than other options they might have, and you will likely be a considerate landlord, which would make you and your tenants happy and comfortable with the situation.
Being a landlord is not inherently evil, nor is it inherently a complicated and frustrating existence. In fact, the world could probably use a lot more nice, considerate landlords. You could be one of them!
Since you have 5 speakers, one of them should be the center speaker, which is focused on dialog. Some Denon receivers have a ‘dialog level adjust’ or ‘center level adjust’ setting that you can turn on and then turn up the dialog level. If you don’t have that setting the solution is to try to turn up the center speaker (or turn down all the other speakers) some way, such as using a mixer or some such (may require some research for specifics).