I have no idea what F-Droid is, but I tried them all and I actually like the UI of the official app the best. It's missing a few features, but they're still improving it and integrating all the features.
I've been using Moshidon, it's based on the official app so it has the same UI, but it has a lot of extra features (following hashtags, viewing federated timeline, viewing timelines from other instances are the main ones I use that were missing from the official app).