It's relative to cminor; the key of champions.
My question to you is this: what do you "LIKE" about the improv?
I like that it looks like you are enjoying your improvisation process. But..... you know when freely improvising it is not something that necessarily is worth sharing with others and in fact sometimes what you feel while playing it will not really present listeners with anything interesting at all. It doesn't matter if your improvisation sounds bad unless you aim to give listeners something enjoyable to observe, personally I improvise mostly in private and rarely share it with others, it is my personal meditation and not always something worth sharing because its benefit to me is a deeply personal one and doesn't require any observers. So if people like or hate your improvisations it makes no difference. There is also an improvisation section to this website:https://www.pianostreet.com/smf/index.php?board=31.0
Nah, I disagree. It takes *balls* to improv something and share it with people. That's more to admire of someone than 'keeping it to themselves'.
....more often than not the feeling you get while improvising is the real reason you are doing it and the sound that is produced is really secondary.