Honestly we can keep to the 3 actions a rule limit, but setting up a framework like that, while done with good intentions, is easily subject to abuse. I mean, if we're really going by the D&D idea that each turn is 6 seconds and 10 turns is a minute of combat, then it'd be better just to play by that logic as oppose to trying to combine 6 second timeframes and the potential of making use of 3 actions. Honestly it'd just make more sense to just use common sense as to what you can and can't do in under 6 seconds of combat. I mean, if your opponent is respectful and you're not being a jerk then you'd only be pulling out extra numbers for the sake of some collaboration move or to even the odds.
And if you pull out some extra peeps, then expect the opponent to do so as well via summoning sentient ninja animals or something that also have their own skillsets. XD I mean, this whole thing shouldn't be a real issue so long as people don't feel like it's a hard and fast rule. Cause if they view the rule as a limitation then they may just try to slide past it to stretch things a bit. I mean, just look at how often people try to figure out exploits as a form of personal challenge in competitive formats. Besides the fact that more numbers on the opposing side can be a form of balance when taking on a really crazy strong opponent. But in the case of someone just pulling out extra numbers for an advantage then the
http://tvtropes.org/pmwiki/pmwiki.php/Main/ConservationOfNinjutsu should be in effect where either the team with greater numbers does less or holds back for the sake of balance, or the team with lesser numbers gets incrementally stronger to achieve similar balance. That way things can be fun and challenging for everyone without some weird 3 move rule.
So I'd have to go with Kayenta on this one. In response to Isaribi's concern for people speed mongering, that's already happening anyway. The only thing is, there comes a point where you become
too fast. I'm talking lightning armor speeds here. The point where you pretty much outrun your own ninjutsu techniques. Sure your handseal weaving will be faster, but what's the point if you just move faster then that projectile you plan to lob at the opponent? Also if you don't stop to release said jutsu and then move in a different direction outside of it's path, you'll just end up firing a jutsu and immediately crashing into it like an idiot, which by that point forces you to at least stop in short bursts. Speed at that point merely just turns into a way for melee fighters to get in range of a ranged opponent. Besides the fact that the natural counter to speed is defense. I mean, it's even prevalent in the show with fights between Lee vs Gaara and Sasuke vs the Raikage. And if your attacks end up being too fast
and strong, to the point where it immediately bursts through whatever defenses the opponent has, I think you need to re-balance said skill. There's a reason why Haku's all directional needle attack is composed of a bunch of thin sharp needles.