[Powers] Melee Cone?

[Varyon]

Apologies if this has been answered before (search showed up some mentions of it but no resolution), but how should one go about making a melee cone attack? This could be a sweeping sword of fire or similar. The easy solution would be to combine Melee Attack and Cone of the appropriate width, but RAW explicitly disallows such a combination. I can do a melee area effect (whirlwind-type attack) with a small Area Effect and Emanation, but no such luck with Cone. The closest I can think of - and I'm not certain this is RAW legal, as you aren't allowed to decrease Max Range independently* - would be to set 1/2D=Max, then reduce Range all the way down to the appropriate Reach. Of course, for a proper "melee attack" you'd want to add Blockable -10% as well, but that's optional. Is this actually a RAW legal option? If there is no RAW legal option for making a melee cone, what might be some appropriate pricing for a houserule?

To do either with Natural Weapon, I'm thinking you'd buy the Ranged +100% Enhancement, then build things as above. Is this correct?

*Technically, this build would be increasing 1/2D until it was equal to Max, then decreasing both down to the appropriate level, but that has the same effect - and same cost - as dropping Max independently would.