As one of the main Mastodon developers, I can't promise you that Mastodon will be a complete and exact Twitter replacement for you, but it may fit your use-cases, at least it does for me.

Just keep in mind that it is not exactly the same thing, some core design decisions are different (there isn't an unique centrally-governed website, but many interconnected servers operated by different individuals and organizations) and thus the tradeoffs can be different as well.

While I personally don't think Mastodon should aim at being an exact replacement to Twitter, I do hope Mastodon can be useful to more people wanting an alternative to Twitter! And I know there are lots of room for improvement, on things we do know, and on things we don't.

Also keep in mind that Mastodon is developed by only two core developers payed through a non-profit funded through sponsorship, grants and donations, so please be patient!

if you maintain a mastodon fork that does not closely follow mastodon main, or the stable-3.3 or stable-3.4 branches, and you're worried the security patches might take some work to apply to your code, hit me up and i'll try to have a look ahead of release (i will not give you the patches or any info about them before release, but if i find the time to do so i can adapt them if they need work)