I like Mastodon (and I wish more Twitter users would switch over!). I wish Lemmy was as polished as Mastodon. For example, Mastodon has the rel="me" profile link verification while Mastodon does not.
I hate that a single company controls all of Reddit.
Reddit really benefits from the network effect of having many millions of users.
I'm not sure how Lemmy instances will end up paying for themselves, but it they don't allow images or video, it might be supported with donations.
I wish Lemmy integrated with Mastodon more. For example, I should have a single login for both, when they have the same host!
Lemmy needs better ways to discover and organize communities, even more so than Reddit does!