I don't find this one to be as good as the first game. It's still fun but it's just not the same
Starting with what's better:
It looks better, it really does, I play on pcsx2 but footage from PS3 looks really amazing.
The cast has some nice additions, and Mobile Armors are another nice thing to add, although it is incredibly sad that they included fucking Seed Destiny instead of Seed.
It adapts way more stuff, more Z and ZZ missions, and Char's Counterattack, that's nice.
Now, to the negatives:
The combat doesn't feel as good, they added stuff to it, some are good, like the air musou and 6 hit combo, but others, like the new clash system and the possibility for "infinite" air combos just make the game less challenging and more tedious, and the change from musou with different stages if you had more meter to just longer versions of the same musou make it WAY more boring.
Even though they adapt more stuff, they also removed cutscenes because...... i don't understand it either
The original stories are, to be frank, completely shit, no more of the what ifs you had in DWG1, now you have RNG fests with the occasional scripted fight, and even those are not as interesting as the ones in the first game. The RNG allows for the new Friendship System, and I like that, but for the love of god keep that outside of the story mode, I just want my beloved what-ifs back.
The voice acting is not as good, this is probably because the actors weren't given a lot of directions, since the story was non-existent.
This may be the case with some characters in 1, but in this game there are characters that are incredibly mischaracterized. I like Kira and Athrun from watching Seed but I just wanted them to shut up, the generic lines are way worse, and theirs are the worst offenders.
In conclusion, suck my left testicle

I find it amazing how even after the additions that came with the following games, all of them still fall short in comparison to the very first one.
This one has it all, an amazing soundtrack full of bangers (Heat to be filled with, All for one and Dead end are good examples), excellent voice acting, both in japanese and in english (well, Puru's is not always the best, but Kamille's, Jerid's, Scirocco's and Domon's are extremely good), beautiful maps (like the Mausoleum or the Satellite Elevator) and a fun combat system that isn't too fast, nor too slow.
The Official Mode is good and has various iconic battles from the original Gundam trilogy (the A Baoa Qu battle always left an impact in me) and the Original Mode... well..
It's simply amazing, a bunch of teams consisted of various characters from different Gundam animes. Good missions with great battles and fun and sometimes even emotional interactions. There isn't a single bad team in the game, but the best one is easily Domon's, consisting of Domon Kasshu, Milliardo Peacecraft and Elpeo Puru, it has the best moments, best battles and best interactions.
The only real complaint I have with this game is the outdated cutscenes (but that is more a product of aging than anything else) and the relatively short cast.
Unfortunately, the games with a bigger cast fuck it up. DWG2's battles consist of an RNG fest with few good moments, DWGR is also fun but it doesn't have the same charm, and I haven't had the chance to play DWG3.
This game was my childhood and it still holds up.

It has some fun stages (like, 2 or 3), but the rest is either uninspired, like the "grinding rails for 2 hours" simulator or the side scrollers, or straight up horrible, like that the stage where they introduce the music notes wisp
OH SPEAKING OF THE WISPS!
fuck them and whoever implemented them here, at best they are "ok" and at worse they make me want to kill myself
I actually like the movement in this game but the problem is that they like to make stages that misuse or straight up ignore it.
The soundtrack is, good-ish i guess? It's easily the best part in this game, but it's nothing special

Now that I've finished all that is currently available, I can confidently say that this is nothing less than a masterpiece and one of the best games I've ever played, no I'm not exaggerating.
The foreshadowing present from the start, the characters, the plot, the backstories, almost everything is perfect here.
This game broke me in a way that nothing else ever did and I completely love it
I really don't know how they will keep up the quality of the writing for 3 more routes but honestly, I can't wait for it.