Aria of Sorrow is undisputably the best of the GBA titles by a significant margin. Circle of the Moon is good but it's an early GBA title and kinda rough. Harmony of Dissonance is the worst IGAvania and you're not missing much by skipping it.

Of the DS titles, Order of Ecclesia is my fav, though exploration is fairly limited for half the game and it's the most challenging out of all of these imo. Also Shanoa is my fav protag of the series (and clearly the inspiration for Bloodstained's Miriam). Portrait of Ruin is pretty close to top for me too, I think it's a bit underrated. Dawn of Sorrow is okay, it does have some cool stuff but 1) the shoehorned touchscreen seal system is deeply unfun and by far the biggest problem, 2) the castle layout/progression is awkward and has a bad flow, and 3) going from the beautiful and unique character illustrations of Aria to the generic template anime designs of Dawn is quite jarring. But it does have my favorite bonus mode of the series so at least there's that.

If you have access to Bloodstained, that's quite good too. It plays like it's Aria of Sorrow 3.

The Lord of Shadows series is its own thing, more akin to like God of War. Mirror of Fate is a metroidvania but it's quite mediocre.