Yes, a keyword action is technically also a keyword, but it's not possible for a creature to have a keyword action without having some other ability
Since you can run up to seven copies of the card in a deck, its likely that Wizards is planning to release seven of these in total
That also means cards that reduce the costs of activated or triggered abilities, like Zirda, The Dawnwaker, dont apply
That seems like a minor quibble, but when you only have a handful of types, your odds of having something on-hand to deal with a type weakness, or something that would suffer from one, is much higher
I've done counters with only four cards, but I just finished a Frantic Search that used thirty copies