Favorite coffee

I know this topic gets discussed ad nauseam here. I am about a month into Moka. I have a three-cup Alpina and a 9-cup Express. I've enjoyed the ritual, trying different coffees, and the coffee itself. I feel like I have pre-ground Italian brands I get from the grocery store dialed in (Kimbo Export, Lavazze Crema e Gusto, and Illy Traditional). When I overfill the basket the coffee tastes muddy. But with a level fill, and pre-warmed water in my 9-cup (the 3-cup doesn't seem to matter pre-warmed or not), I'm getting a nice, strong, tasty cup of coffee.

I've been eyeing a stupidly expensive burr grinder. Are other folks buying fresher beans (or even these Italian brands in bean form rather than pre-ground)? I also have a Chemex and I suspect if a burr grinder really is all that it will improve the Chemex flavor.

Are there others who just buy what's there and enjoy it - or do I just have an unsophisticated palate, haha?