iternabe Thanks for your response. I appreciate it.
My set-up is designed so I can use it in conjunction with my practice, hence I didn't mention headphones. I have some Grado 325sx's, and yes, the sound is much improved through them, but as I'm listening while practicing, turning the recording on and off, stopping at problem areas and working on them, then listening some more, etc., I find the Edifer speakers more suitable to my purposes. I'm not recording for other people to listen to, just for me to approximate what a listener might hear so I can see where I hesitate, where my articulation is uneven, how consistent my tempi are, where I'm using too much rubato, etc.
I have tried placing the Yeti mic in lots of different places, in and out of the piano, and the best placement so far has been inside the piano about 1/2 back from the front, in between the treble and upper treble. Putting it outside the piano has always resulted in inferior sound.
I know better speakers would help, but it's a balance between the convenience of a blue-tooth & usb setup on the one hand, and a more complicated arrangement of better mics and better speakers. My current arrangement is light-years better than the crappy Tascam recorder I was using!
I'm also relatively naive about the intricacies of GarageBand. I know it is overkill for what I'm doing, but I don't really know of a simpler alternative. For instance, I can adjust the gain a little in GarageBand to improve the sound, whereas adjusting gain at the Yeti even a little results in clipping. (I'll try listening through my Grados and seeing if I can adjust the gain better.)
And as I said I have tweaked the equalizer to maximize piano sound.
I can live with my set-up fine, but all the responses here made me think maybe someone has a way I could tweak things or do something different without going whole hog into sound engineering. 🙃