Tusky is best for those who are newer to Mastodon. Visually it’s very clean, straightforward to use, and largely free of bugs (it helps to have been around for so many years).
For users more familiar with Mastodon, I’d go with Fedilab. Despite a few bugs, it’s the most customizable option, with so many features you can tweak to your own tastes.
I will add that many of us who work remotely using publicly accessible wifi also use VPNs, and Imgur actively blocks IPs from multiple commercial VPN providers. If you want those users to see the image you’re sharing, Imgur is not the way to go.
Pixelfed works well with other Fediverse services like Kbin and Lemmy. Try hosting there!