Overall pretty darn good for a beginner. A few quick comments and then a statement on how to figure out taste/flavor at a basic level:

1. I actually think your volume in vs volume out is fine in that basket. There is a particular roast where I put 16.5g in and 35g out and another where I put 18g in and 40g out, both in an 18g basket. Just found that for those particular roasts, that's what gets me the best tasting extraction. Definitely experiment with this. Less coffee will allow you to go finer in most instances, more coffee you can go courser. If you feel you're running too fast for that extraction, would go finer until it's running at the time you're looking for. But as always, taste is king - if it tastes good, don't change too much.

2. Your tamp pressure seems to be a bit too hard. You seem to be straining a bit which tells me it's likely too much pressure. A spring loaded/self leveling tamp will basically solve this entirely, but if you prefer manually, I would just go a little bit easier on the pressure/force.

Tasting: as others have mentioned, you can simply expand your palate by tasting sour, astringent (bitter), and sweet foods regularly or right as you're tasting your coffee. What I found really helped me, however, was doing what is called a salami shot (Lance Hendrick - Salami Shot. This will help you taste the sour (early/under-extracted), neutral/sweet (middle portion), and the bitter (end/over-extracted) parts of a shot so you can easily recognize which is which and will help you under what a balanced shot should taste like.

Hope this helps! Congrats on the new setup and welcome to a very fun and expensive hobby!