Where to even begin...
The cons and some comparisons to the original:
They have sacrificed core mechanics of the game in favour of historical accuracy despite never being a historically accurate game in the first place. The native civs can no longer tame animals, which was one of their coolest features, and the North American natives can no longer mine and are required to construct an additional building to be able to acquire coin. Changing things in the game to be more accurate and considerate towards people who were presented in the game in a way that was ignorant or even disrespectful is fine, great even, such as changing the names of the civs to what they actually call themselves, but changing core mechanics and lazily introducing them is not. This is an absurd and unnecessary change that is an insult to veteran players.
A major pet peeve of mine is the change from colonial era to commerce era. Are you trying to tell me that a game, that is built around the theme of colonialism, around the era of colonialism and who's entire gameplay is based around building a colony can't have the colonial era in it because it is too offensive. Was colonisation an awful thing for many people, YES, absolutely, but it happened and its what the game is based around, the game isn't making it out to be some glorious thing. This change of course does nothing to the actual gameplay so I'm not going to give up on the game just because of that but it is extremely idiotic and useless.
Home city progression has been almost completely removed. You can still level up your home city, however, it only unlocks the customization options for the visual appearance of your home city and no longer unlocks shipment cards, as you now start with all of them. While this works great for multiplayer as you no longer have to grind of out matches to get the cards you need to stay competitive, it is awful for singleplayer. There is no more sense of progress or goals to work towards and the main replayability of singleplayer is simply gone. This is the change that makes me just not want to play the game, I used to love unlocking and experimenting with different makeshift shipment decks as I worked my way up to the more powerful ones, but that is no more.
The UI is a complete and utter joke. The visual design of it looks as though someone made a bunch of text boxes in Microsoft Word and copied and pasted them onto the edges of the screen. The original AoE 3 had a UI design that was full of character and had amazing satisfying sounds to match. The definitive edition UI is completely soulless and had ear-piercing horrendous sounds mixed in with some rehashed sounds from the original version that somehow sound worse. To add on to this, the deck editing menu is nigh unusable, its essentially just a massive blob of the possible shipments you can use with very little sorting options. The original deck editor showed you what building the card type, what era you could get the shipments in and the progression trees all at the same time, allowing for easy location and identification of each card. In the definitive deck editor you can sort by age or by card type thats it, enjoy, and the cards are in a seemingly random order with no visual separation making it a long unsorted messy list of shipments that fit said categories.
This only what I've discovered and thought worthy of mentioning in my mere 2 hours of playing the game. I've hear many other people mention how poorly optimized the game is but I have had no issues with performance as of yet, so be cautious in checking if your pc can actually run the game.
The pros:
The two new civs seem unique and interesting, haven't played with them enough to say for certain but I'm not really picky with how strong or standout they are, just happy to have new content.
The graphics are a decent upgrade, nothing ground breaking but they generally look nice.
Having achievements is nice, there aren't a lot of them but something is better than nothing at this point.
It's cheaper than the original AoE 3, which is nice.
yeah, that's about it, it's a ♥♥♥♥ show.
The Meh:
The sound revamps are overall higher quality and are likely more accurate but they take away a lot of the nostalgia of the original and are also a lot less satisfying (in my opinion).
The long list of changes to the native civs are great for recognising and respecting these cultures and for the most part don't really affect gameplay, however they ruin a lot of the games nostalgia (which is admittedly a sacrifice I think we can make) and a lot of it is lazily done, such the community plaza, where villages walk in circles for some reason and it looks ridiculous. The fur trading building used to get coin is gathered by villagers as if they were plucking berries... from the side of a building... built next to a coin mine... which they aren't allowed to gather from... but the fur trade drains coin from the mine? Very historically accurate, thanks devs. It's just looks stupid and is clearly not very thought out, but once again, doesn't affect gameplay so it's not that big of a deal.
Things they could change to make this better:
Major problems:
A big one would be to revert the any and all mechanic gameplay changes (not balance changes). I can understand if they don't want to do this because they have committed to it and don't want to insult the very people they changed it for.
Add the option to have level unlocked shipments and restore the progression mechanics in singleplayer
Make the deck builder the way it was in the original or add more features to make it less of a nightmare
Minor problems:
Add the option to use legacy sound effects
Allow for more in game UI customization
Make the main menu UI less of steaming pile of ♥♥♥♥♥♥♥
Summary
I'm pissed off. I've played more hours of AoE 3 than can possibly be counted, accumulated over the span of over a decade and to see it's legacy end with this disappointing mess makes me extremely sad. I've been beyond hyped since the first Definitive Edition was announced as I was hoping that AoE 3 would get one, and I was even more hyped when AoE 3 was confirmed to get one. I am not hard to please when it comes to remakes, I would have been satisfied and given this game a positive review if it was simply a graphics upgrade with nothing else but they went ahead and made changes that no one wanted, removed content and sucked the soul, the character and the passion from the game, all in one fell swoop.
Some additions after seeing the comments:
People are thinking that I'm railing on the devs for giving in to offended people, I'm not, I'm fine that the changes to the names and appearances of the nations, buildings and other things make the game more inclusive. What I am not ok with is compromising the gameplay for the those reasons. It's likely my fault for giving off that impression as my paragraph on the whole colony renaming ordeal made it out to be a lot more serious than it really is.
I don't want to hate the game, I don't want to see it fail, I want to enjoy it. In it's current state, however, I don't see myself playing much of it and I would love to see that changed.