Pleurothallis grobyi is probably a good choice, as is Pleurothallis sonderana. Both stay fairly tiny, and produce clouds of blooms. Good luck!

Dracula spp.
- Dracula lotax
- Dracula inaequalis
*** The smallest of the Draculas to date. ***

Dryadella spp.

Masdevallia spp. (this includes all the recently subdivided genera that used to be classified in Masd.).
- Masd infracta
- Masd nidifica
- Masd wendlandiana
*** These species stay fairly small and are intermediate to warm growers. ***

Platystele spp.

Pleurothallis spp (this includes all the recently subdivided genera that used to be classified in Plths).
- Plths ornata
- Plths breviscapa
- Plths tribuloides
- Plths decipiens
- Plths grobyi
*** In my opinion these are great beginners micro-mini Pleurothallis. ***

Porroglossum spp.

Restrepia spp.
- Restrepia brachypus
- Restrepia muscifera
*** Most Restrepias are pretty easy to grow, but these are the ones I've found to be pretty sturdy."

Restrepiella

Restrepiopsis spp.

Scaphosepalum spp.
- Scaph rapax
- Scaph ovulare
*** In my opinion, not necessarily the best for those who haven't grown micro-mini Pleurothallids, but they're not that difficult to grow. ***

Stelis spp.

Trichosalpinx spp.

Some of these grow better mounted. I've found micro-miniatures to be difficult to grow potted.

If you're going to try out Lepanthopsis astrophora (which I think is easier to grow than Lepanthes spp.), I think you may have your hands full at the moment until you learn what it takes to grow them properly, before I can even recommend something like Lepanthes spp.

I can only recommend Lepanthes spp. to those who have a bit more experience with growing Pleurothallids under their belts.

Trisetella spp. are also something I wouldn't recommend to someone who hasn't grown Pleurothallids before.

There are many other micro-miniatures, but they don't belong to the Pleurothallid Alliance.