Are you asking for us to choose which one we like out of those three? Or are you just looking for general opinions on those three, or other stocking ideas?
I personally like the first one the most, mainly as I prefer tanks with fish at all three levels or at least has some sort of bottom dweller. Some quick google research shows that you may want to consider getting more than one of the SA bumbleebee cat, three seems to be the recommended number based on a few different sites I've been too.
The all tiger barb tank would be an impressive display, although I do believe that they are better suited to a 3 foot 30 gallon aquarium due to how highly active they are.
The dwarf puffer fish tank certainly would be a very interesting and entertaining aquarium, I love how they have personalities and are very fun to watch! That would probably be my second choice.