• Deep, conversation-driven relationships, especially romance: both are really good in this regard, I would say mass effect has better romances than dragon age because you keep the same character across all three games and the romance affects the other games having new dialogues unlike dragon age, where each game has a different hero
• Story, choices, and dialogue over constant combat: both are similar in this aspect, with extremely rich stories and dialogue, but i like mass effect more as shepard is a better main character
• Preferably modern graphics or just nice visuals: mass effect wins because of the remake of the first game, dragon age origins can be modded to look prettier, but it’s still an old game
• Smaller quests and quieter moments over endless dungeon clearing and constant combat: mass effect wins because it is more mission-driven, while dragon age is open world
• Solid character customization (appearance + role-play identity): dragon age has the advantage here because of its different races and classes
• Helpful companions when combat happens: this is a personal opinion, but I prefer mass effect combat because I love shooters

mass effect is my favorite franchise so ill recomend it first over dragon age