just got done playing through every mass effect game, below are my thoughts on 3 as it is still fresh in mind
the good:
i greatly enjoyed the combat and feel that it is the best of the series its fluid and faster paced, way, way more weapons, no arbitrary restrictions on what you can or cannot use, the powers are very fleshed out and fun to use regardless of class
the consolidated paragon/renegade morality system is how it should have been done from the beginning giving greater opportunity for roleplay and actual decsion instead of blindly following the pre-determined paths
killing 300,000 batarians is made canon, the objectively best part of mass effect 3
the bad:
cerberus fighting against you from day one is so out of character it feels like the writers at bioware hated that anyone even remotely agreed or liked them and were like 'NOOOOOOOOOOO! YOU CANT LIKE CERBERUS THEY'RE EBIL SPACE NYATZEEES!' despite the fact cerberus hasn't done anything any other race's black ops hasn't ro wouldn't given the opertunity, looking at you STG
the squadmates are lifeless and uninteresting, further more there is literally no reason to speak to any of them, unfortunately even garrus is significantly less cool than in previous games, for a game series that is at bare minimum 50% character focused tanks the experience beyond words
ironically the game with the best version of the morality system is the one least equipped to exploit with it, every dialogue option is paragon or renegade, upper right or lower right, no neutral options at all, maybe its because the writers were fed up with people only really going for paragon options that they threw up their hands and said 'why even fucking bother?'
the side fetch quests are me2's scanning for upgrade materials but somehow even less engaging and more annoying
legion is killed off for no reason
no exploration of the effects of indoctrination on a galactic war, given that any exposure to reaper tech leads to indoctrination
the ugly:
the map only has markers for n7 side quests and main quests, fuck you if you want to find to elcor homeworld, you'll have to search every fucking system and constantly reference the quest log to find anything at all
liara is completely useless
every cool bit of lore from me1&2 are completely thrown out the window, reapers are just some rogue ai that trying to 'preserve' organics from wiping themselves out by creating synthetic life, 3 also tries to retroactively assert that organic-synthetic conflict is what the series was always about
the heavy handed """ptsd""" dreams of the retarded kid and anyone who died in the suicide mission, clearly the writers were expecting you to get most or all of them killed, as evidenced by the genisis 2 dlc, wherein most of the companions die irrespective of your choices, which in game is a really, really hard thing to do and i've tried
kai leng, so pointlessly edgey, the game is improved by so much if he's removed
no choice you make in either previous game has an impact on the third, hell the biggest impact is whether or not you can make the suit-rats to not be retards and make peace with the geth, and even then its only a ~100 point difference, same with curing or sabotaging the genophage, there is minimal practical difference, the war does not last long enough for there to BE a difference
building on the last point, the crucible feels like its built in a week, there is no sense of time passing and it gets completed even if you ignore everything outside of the main quest and the only thing doing the shit fetch quests net you is a higher warscore which gets you is an extra line of dialogue and a green ending light at fucking best
the """""""endings""""""" are red, blue or green colored lights and minor variations in cutscenes
the crucible should have failed and done nothing or actively been detrimental, and harbinger should've appeared before you and said 'you have failed, you evolve along the paths we determine', y'know a MAJOR FUCKING PLOTPOINT OF THE SECOND GAME and mocked you for even trying to defeat the reapers
the writing, ending and contrived plot bring what was an 8.5/10 down to 5/10 and i'm still mad about the ending, even 13 years later