If it’s tasting good, you may be grinding more coarsely than you expect, but not too coarsely to extract the coffee well enough for you to enjoy. I suspect a lot of folk grind too finely in a bid to meet arbitrary/consensus shot times, or for aesthetically pleasing shots. Taste preference trumps time.
Either way, I wouldn’t give it too much thought unless you stumble across consistently better shots elsewhere and decide you want to pursue those.
The “best ratio” is just the ratio that suits your grind setting & your preference in extraction at that ratio (strength/concentration, put simply). If you aren’t plagued by sour shots and don’t need to go longer & weaker, then that is the “best ratio” it might be 1:2.1 for you, 1:4 for someone else.
If you did like weaker coffee, you would likely be going longer on the ratio.
Extraction preferences have a tolerance for a specific bean, it’s a bit wider for a range of beans, so nailing an exact & narrow extraction range for a bean isn’t really necessary, there will be a lot of overlap, but Brazil, Costa Rica & say Guatemala may be at the lower end with Colombia & African beans at the higher end of that tolerance.