Avira was good when tweaked when I used it. CIS is maybe a bit better, which requires tweaking as well. Both are flexible, but CIS more so.
The free version Avira I use has absolutely no "tweakability". It may be a similar experience to buying discounted fireworks late on the 4th of July. Maybe we just get what we pay for. I can't complain that I've picked a Dud since it's free!

It does have (3) buttons. (1) for "Scan Sytem", another to "Start update", and a very special (1) with the word "Upgrade" I just tried for the very first time! Pushing this button felt dangerous

& FUN like something out of "Alice in Wonderland" IE: "Drink me!" or

"Eat me!", lol!

Here's what we find "going down the rabbit hole": "Stronger antivirus, protection for tablets and smartphones as well as 5GB of online storage. (..& another button!!) "Upgrade to Avira Antivirus Suite $44.99".

I think I'll wake up now.

*ooh,

actually (after reading Umbra Polaris' comment) I'd found the "tweaking" rabbit hole. (..just had to look to find the engine's hood!)