The main 6 blind bags in any form dont tend to do too well unfortunately. Although there were slight difference in their later glitter releases, the fact they got a very similar release in the boxed set (with Emerald Rays)...a set that to this day clogs up the shelves on my local Tesco store...knocked the price on the glitters quite badly. I would give it a go at $5 for the wave 1 and $8 for wave 2 but be prepared you may have to pop them together in a lot. ($2 for wave 1 and $5 for wave 2 may be more likely).
Like harder to find ponies, harder to find petites can go unexpextedly high if a couple of people are trying to track down that one item at the same time. $40 is high for her. However I will admit if I still had some of the harder to find petites I would probably be selling them now as they are at a bit of a peak.
Twinkle petite - I would normally have said $6ish but right now I think you are back up to the $20 mark (they were at $15ish a year or so ago and then plummeted but they have certainly recovered). Some of their auctions are very high so that may be a better bet for you?
Ponytails and pony parade will be $2-4 each.