Before Snapseed there was Camera+. Its photoediting features are a lot better than Instagram’s, and even though it’s not as fully featured as Snapseed, you might like it more because it’s cheaper and bit easier to use. Other than the great filters provided, the best thing about Camera+ is the ability to capture photos by setting the exposure at a different point than the focus (something most camera apps don’t let you do). For only $0.99 Camera+ might be the most cost effective Instagram alternative.
Here's what I think you'll find: Mastodon users are nice people. The wider federated network has posts in English, Japanese, Spanish, and from techy open source enthusiasts. It's way more queer and trans-friendly. Neurodivergent users are out and proud. Furries are all about it. I'm seeing more and more amazing artists posting their work. Sex workers exiled from other social media have even made their home on a Mastodon instance.
A simple chat (slack style) it's enough. Just having the possibility to send messages either single user or team (#channel). But please don't forgive to give an useful appeal to mobile app (worst error of competitors is, have a good app but totally no mobile friendly!) i would expect to have a similar whatsapp or slack app for messaging within the slack mobile app!