Things that remain to fix, and some proposed solutions, presented in patch lingo/analytical lingo:
-AI happiness buff should be reduced.
-AI should do less ICS, and instead escort and guard their settlers more (and maybe get a settler production bonus if they don't already have one).
-AI should accurately assess its surroundings. Pacachuti seems to go for a cultural win a lot, but he rarely has enough troops to defend his cities, even though his cities all often have castles and walls etc.
-AI should be friendlier to you after you've traded with them, and never offer lump sum gold deals when unfriendly to you (i.e. Nappy's 25 gold for my 2 gold per turn for 30 turns? I'll take his 25 and then declare war on him, making a profit of at least 23 gold lol).
-Boost food resources. Add buildings that gain additional bonuses from having food resources nearby.
-Allow military formations (able to move multiple units at once).
-AI should not be "friendly" to you after denouncing you.
-Boost Great People buildings (i.e. Academy, which remains incredibly weak). Also boost Culture Bomb. Allow Great General to be attached to a city and pump out units with +15 experience.
-Reduce production cost of wonders and buildings, and lower maintenance fees empire-wide by about 15% minimum. This will present the player with more choices throughout the game.
-Nerf El Dorado gold bonus of 500 (Ridiculous, and I don't even have the DLC, but enough people have brought this up to believe that this silly wonder actually exists in the DLC).
-All Natural Wonders now provide 1 culture at least.
-Stable now grants Horsemen a little extra experience.
-UN resolutions added in. One of them should allow foreign trade routes via roads and harbors.
-Hotseat and multiplayer functionality should be added back in. In the very least, single player AI civs should get static pictures to represent them, rather than just a flavorless blank light blue screen.
-Allow Babylon, Mongolia, Inca and Spain to be played in multiplayer. Allow players to tick options allowing Babylon, Inca and Spain in games (or not). Mongolia should always be allowed as part of the base game now (post-patch).