Well, I can report a bit on Ranunculus repens now. I've been using some this week in small cut flower bouquets and have been leaving some out at room temperature to observe. The vase life of the flower itself is very good lasting at least a week in good condition but the stem is another matter. The stems are brittle and also tend to turn into brown mush even while the flower continues to remain acceptable. In my latest arrangements I avoided having tall stems due to concerns that they might flop over. Instead I arranged the flowers such that a nearby foliage plant would support the flower in the event that the stem loses turgidity. The stems seemed to hold up best if I chose only the thickest stems, recut them underwater and then refrigerated them immediately.

I would say that this flower is acceptable for cut flower use but only in small vase arrangements not in celeophane wrapped flowers or mid to large arrangements and not in situations where the stem might get pinched. I didn't bother trying any tests out of water as I'm sure the stem would flop very rapidly.