Pls explain how early summoning spells are useful

[PrinzMegaherz]

Problem with early summons is that you can't get most of them in numbers that actually matter. In addition to paying the gems, you have to keep one mage away from research for one turn... and all that for only one fire drake or one wyvern?

It's sad not every single summon spell has it's higher level equivalent like summon wraith and summon legion of wraith. The later is much more useful than the first