Combat in DA:O (on PC at least) doesn’t feel too dissimilar to BG combat. Warriors and Rouges get a bunch more skills to make them a bit more interesting to use, and the core mechanics are different, but it’s very similar in terms of issuing commands and setting companion behaviors.
I think DA:O has more to do with KOTOR, then Baldur's Gate. And honestly, if DA:O was a 20-25 hour game I might have found it alright. I will put aside my issues with content and focus on combat itself.
I found abilities simply too spammy. Cooldowns are literally couple seconds long, and with multiple abilities it is difficult and tedious to control all characters. I didn't find myself using skill tactically, and when I did they were very repetitive (like trap spellcaster with the crushing trap spell). Using custom AI wasn't really an option for me, as 1) not playing the game is not fun for me. 2) if I tried it I would usually find myself out of ability when I need it. So DA:O was tediour, but shallow combat experience, which clunky and unresponsive controlls - with the way characters walk through each other one can even properly space-control. Add to it, that shallower mechanics lead to repeptitive combat, as the game isn't able to conjure varied enough enemy types for players to fight. I just never found myself asking "what should I do" in DA, and that kills a game like that for me. I had same issue with Tyranny, where one simply wanted to use abilities everytime they were on cooldown, making the whole thing feel like tedious management, then tactical combat. Luckily I liked everything else about Tyranny.
I suppose the biggest boon is Dragon Age presentation, but that is also something I never liked. I see appeal of Mass Effects well animated and directed conversations, but zooming in on poorly animated doll, doesn't make things better for me - I would rather stay zoomed and use my imagination.