It is very rare to see RPGs where the characters have multiple different abilities they can choose from that have no cost. In Dragon Quest 8 though, three of my four characters currently have such abilities. For example, Yangus has both Steal Sickle and Wind Sickle, neither of which cost any MP. Steal Sickle is a regular attack with a minute chance of stealing an enemy's item, while WInd Sickle is simply a potent attack. The nameless hero has Dragon Slash, Flame Slash, and Metal Slash, all regular attacks that are effective against certain opponents. These attacks are functionally replacements for the basic attack command, but they significantly increase the tactical options for the player.
A good example is with my current setup for Jessica. Her main weapon is a whip, so she can attack a group of enemies with her basic attack. However, I also gave her the Blow Kiss attack, which does damage equal to her normal attack against a single enemy, but with an added chance of charming the enemy so that it doesn't attack. So, there is a trade-off to made when choosing either attack. Her basic attack is good against groups of weak enemies, while her Blow Kiss attack works well against single strong enemies. I think it allows for much more interesting combat choices than a system where only basic attacks are free.
Other notes on the combat system so far:
Attack magic seems somewhat weak so far. Spells seem to only remain useful for a short time after I acquire them, then quickly fall behind physical attacks in effectiveness. For example, the Boom spell was very useful when I got it, since it did comparable damage to a normal physical attack against all enemies in a battle. However, it currently only does about half of the damage most of my characters do. Only one of my attack mage's spells can do comparable damage to my main fighter's attacks.
On the other hand, status spells are surprisingly effective. Group confusion spells are particularly effective, and DQ8 actually has an instant death spell that consistently works. I like this very much, since it increases my tactical options significantly, so I am doing more than just using basic attacks every turn when fighting regular enemies.
I will probably have more to report as I get deeper in the game. Right now, I am neck deep in gambling in the game, so I might talk about that a bit some time soon.