The ones in yellow are because our simulator doesn't handle beam-attacks and autofire correctly yet. The green means it was tested. The blue on white means the attack qualifies as Periodic due to its Rate of Fire.I believe the rule will be that if you can fire more than 1 Periodic attack per Round, any Round, then you must pay 1/3rd the cost of your full-price attack for each such back-up attack. I'm still not sure exactly how to phrase the "1 attack for even Rounds and 1 attack for odd Rounds" combination (I could just say that but I think there's a larger issue at work).
This is the same as Thomas' notes about attacks that work on "different clocks." Yes: if you have one attack that works every other round and a second that works "in the gaps" you don't get the second one for just 1 AP. So as I said above, we need to figure out how best to address that.
On the other hand, there are some things we do want to encourage.
Some Notes About Range
Thomas notes that there's a big difference between having a lot of ranged or hand to hand attacks vs. a mix. That is true--but it's a distinction we want to encourage. Why? Well, a few reasons. The first is that we feel flexibility is a net good for the game. Even though some characters will come out better than others (the strong guy with laser vision is 'better' for just 1 AP than the strong guy with +1 Strength) we feel that that's a feature, not a bug.
Does it mean everyone will have a ranged attack just because? Well, maybe. But our experience shows that's not the case and even if it was that would be okay by us. Our experience with a multitude of games suggests that the general best build is to find one thing to do in combat and excel at it so having there be a few good alternate modes doesn't seem like a problem to us.
It's also true that in our tests even 1 AP can make some significant differences at moderate AP levels so if that extra attack takes the place of, say, an extra point of Armor, for example, that's a serious trade-off.
What Else Might We Encourage or Not?
Attacks that ignore armor are a gray-zone right now. If for +1 AP you get the ability to ignore armor that's a pretty significant strike against Armor. Now, granted, right now Armor is "the best defense" (in quotes because it's definitely not always true but is true enough to be a concern)--but the legion of armor ignores would be a problem.
Allowing you to pay 1/3rd AP-cost of your most expensive attack for an equal Ignores Armor Attack seems fair though. That's a big price to pay.
Attacks that mix damage with Resisted Attack effects are also suspect: they have special bite against low-DP targets (especially if the RA effect ignores armor as well). They are also a lot more complex in terms of handling time (there is not just a regular damage check but then the whole RA thing and keeping track of RA effects is non-trivial for the GM if there are lots of opponents). So those might go down as well.
Perhaps there will be an "E" for Exotic attack type which always costs 1/3rd your most expensive attack and is never cheap (even other 'E' attacks would fall into this rule).
On the plus side, though, effects like lightning and burn won't count: having a good mix of these attacks is within bounds. If a character has an Armor Piercing arrow that does less damage than a normal one but ignores Armor if a save is missed we're okay with encouraging that.