One quarter in diameter for several species of Ferraria is flowering size. Typically corms develop one on top of the other in rosary fashion and the rosary is better not divided (will make for larger plants). Better choose the larger ones and pot them together. As you say foliage in all Ferraria species is typical and unlike that of all other bulbs. Deep planting is sensible as the corms bury themselves and are found really deep in pots. A mix with plenty of coarse sand and grit would be great and many species grow in the wild in pure sand. If you have so many, why not to consider give them suitable homes by sending them to PBS Seed and Bulb Exchange.