I disagree here. Using abilities consumes mana, managing mana complicates item purchasing, balancing item purchases against upgrades is a team dynamic. So there's one element of complexity that's removed.
Managing cooldowns, picking whether to creep faster, harass a high HP target, or wait to use it until a kill opportunity comes up is more complex than just right clicking on the fly. It requires more planning.
AA builds are simple, ridiculously so. The build listed in this thread took absolutely trivial abilities just to skip out on grabbing mines. I really doubt that any of the DGs were intended to be played with one hand, and I would wager they'll take means to keep it from becomming dominant, likely through itemization changes (which isn't to say it's currently needed.
AF uses mana. Plus "AA" builds almost always end up using MoB and Snipe as supporting skills, and if you are going to use AF, MoB, and Snipe you are going to tear through mana like you wouldnt believe - you are going have to buy Vlemish like everybody else. So that completely nullifies the first point. Really what an AA build means is that you arent mining, not that you refuse for some strange reason to not use skills like Snipe and MoB.
AA builds generally go AF, EA, MoB, and 1 point in Snipe. I dont consider any of those to be trivial abilities, so I dont know where the claim that they are taking "trivial" abilities just to skip mines is coming from.
I also think it highly unlikely that AA builds like the Reg ones werent intended given that the completely obvious use of the extensive EA line is for an AA build, plus there are a TON of items that increase attack speed. Why have all those items and the EA skill line if you dont intend AA to be a big part of the game?
Taking a build to minimize to intentionally increase your flexibility by not being reliant in large part on cooldowns is a strategic decision that adds depth to the game. Choosing something with flexibility while sacrficing burst damage is an interesting choice, and eliminating tough strategic choices hardly makes a game more complex.