I think this would be amazing. Even just 1 level of nesting would allow for some intriguing ability to consolidate macros. Like for example, being able to use a ?{} markup inside of a @{} markup to select a roll you want to make... hmm that was surprisingly vague. Let me give an example:
Say for example the following is true:
you have an attribute
@{Longsword} with a value of
"2d6" for damage and
@{Longsword|Max} with a value of
"+ 1" for its enhancement
you have an attribute
@{Mace} with a value of
"1d8" for damage and
@{Mace|Max} with a value of
"+ 3" for its enhancement
you have an ability
%{Attack} which rolls the following:
Attack [[1d20 + @{Selected|[[?{Weapon}]]|Max}]]
[[@{Selected|[[?{Weapon}]]}|Max]] is used in this example to bring up the roll query box where you would type in Longsword and it would then return a completed roll of 1d20+1 (the d20 roll and the weapon's +1 enhancement bonus). Where as if you type in Mace it would return a completed roll of 1d20+3 (the d20 roll and the weapon's enhancement bonus). Allowing you to attack with any of your weapons by simply pressing your token action button
[Attack]. Of course there are a great many other applications of doing the same sort of nesting and this is just a very simplistic example. With more complex roll parsing you could very easily set up your macro to ask you which weapon you're attacking with, whether you're applying a feat or ability to it, and so on.
This would allow not-so-clever dm's like myself to create 1 touch macros for their newer players so they can focus more on performing their actions and less on double checking their character sheets. And, likely dm's far more clever than myself could probably pull off minor miracles I couldn't even imagine with something as simple as a single level of nesting of inline rolls. Or even just the ability to nest an ability/attribute/query inside of another ability/attribute/query.
Well I typed more than I had intended to, I think my inner salesman came out there for a moment... excuse me while I go put that FoP back in his cage to play music like the good little minstrel I am retraining him into.
This wishlist item has my vote... if that wasn't obvious already!