Hate to burst your bubble, but I've had this conversation with a pumilio expert many times. No matter what anecdotal evidence I share with them, they still say that there's no brom that's better than another. They have told me that in situ, the frogs show no preference. In some areas they breed in refuse containers- so basically anything that holds water. With all of that being said... I have had great success in years past utilizing the following:
These are good for displays
Guzmania lingulata- my go to brom. It can be found in situ with many pumilio pop's. The regular form can be quite large, so not recommended for smaller vivs. I've used the "minor" form in smaller vivs with success- again with pumilio.
Guzmania musaica- for large viv's only. Also found in situ with pumilio. Holds a lot of water and has a fantastic inflorescence.
Vriesea heliconoides - about the size of Vriesea erythrodactylon and also is found in situ with pumilio. Good for medium sized vivs.
If strictly breeding and you don't care what the brom looks like:
Any small Guzmania or Vriesea hybrid. Why? They are usually cheap and can be tossed. I know a few O. sylvatica and histo breeders that go this route. The bigger Oophaga's tend to "muddy" the cups quicker than the smaller species.
"Sticks and stones may break my bones, but cancer will probably kill me" - Sheer Terror