I've had a play around with the idea of action tokens myself, making a few cards with them (posted here
http://forum.dominionstrategy.com/index.php?topic=17079.0. There are other ideas there as well, I tried making a sort of expansion).
I think the problem with both of those is, why wouldn't you just spend them immediately? Maybe you'd hold on to the +Action tokens, but then the functionality becomes pretty similar to Coin of the Realm. Also, it becomes a lot harder to track Actions if you're spending tokens to get them.
I mostly agree to this. There isn't a lot of difference between them and Coin of the Realm, besides cards that give them not easily missing the shuffle, or being only playable every other shuffle in decks that fully draw themselves. You can also gain them outside of your turn easier, which opens up some new possible concepts. Overall, they're more reliable than CotR, and they can help make engines out of thicker decks that can't trash (or get thick with late game greening) as you aren't as dependant on the order you draw your cards in; for this reason, action tokens work extremely well with non-terminal draw.
For tracking, I've moved tokens into play as if they were CotR and kept them there until Clean-up.
And about card tokens, I'm pretty sure wero is right in saying you would use them straight away, as it's never wrong not to unlike with action or coin tokens. So, I don't think it's possible to make a card that genuinely needs to give them out. If you take them during your turn they may as well just be + cards, if you try giving them to others they're doing Lost City or Council Room, if you give them to yourself after your turn they're Expedition, and for individual cases like Tactician there's already Pathfinding and Teacher.