What can one say, eagles, slingers and kamayuks all wreck in style. You get siege engineers and siege ram for lategame pushes. Their eagles are better against Mangudai and CAs than Mayan 100 hp ones. Anything with less than 13 pierce attack tickle them.
Face franks? No problem, slingers to counter TAs and kamayuks to counter paladin. Easy lategame.
Enemy thinking of skirms or parthian tactics? No no, they have no bonus against Kamayuks.
Face archer civ? Eagles with 10 pierce armor, easy game.
Enemy wants to do infantry? No no, slingers are on the job, and kamayuks go even against champion as well.
Towers, TCs, outposts, castles, stone walls costing 15% less stone is sick and means you can build a tower for you forward gold and still afford another tc! Incas eco bonuses might be weak but there are 4 of them!
Want a fast game? Your enemy has a bad map? No problems, tower rush, eagle rush, its all in your hands.
Get focused in a team game? No problem, villagers are supertanky and even if you build tower or 2, you can easily afford TCs with a bit of stone.
Best thing however is that you have 5 different infantry (villagers!) and 3 archers! Easy upgrading and swapping units! Enemy won’t know whats coming.
Their UU isn’t just little bit better knight/arbalester/CA/Champion, it is anti cavalry infantry that isn’t weak to parthian tactics, infantry or skirmishers! Halbs are crying in the corner!
Incas are awesome, no game is the same. Oh yeah and you get to scout with extra sheep, gamebreaking!