Rorona admittedly was an experiment from a 2D era to 3D. It's definitely not what I'd recommend people to start on. Totori, which I started on, was a decent start for me but left me wanting more. Meruru, the last of that trilogy, is a good place to start if you want something that encompasses the essence of what an Atelier game is: exploration, adventure, and of course alchemy. The battles are a bonus. Those are what I would call the Arland series.
The Dusk series, the most recent ones localized, are a bit grittier in terms of subject matter and gameplay and reach a bit into Mana Khemia for inspiration. Ayesha is bit of a prototype in terms of feel, but it's not a bad thing. It gets you started into what the Dusk series is about, more action, a dying world, and a little more complex alchemy than Arland. Escha/Logy expands on the battle aspect while trying something different with carried items and adding another layer to the alchemy. I recommend this as a starter. Shallie, the last of the Dusk series, goes full out Mana Khemia in terms of battle and the fights get harder quickly. The alchemy again gets another layer added to it, but I feel it's familiar enough if you've gone through the Dusk series.
Keep in mind that the soul of Atelier is the item crafting, characters, art, and individual settings. The battles are series/arc specific in terms of style and development. I say that because Sophie seems to have taken a step back and made the battle system simpler compared to Dusk. I just hope there's an element of strategy in it to give it a needed bite that Dusk offered.
In short, yes, do try other Atelier games. Rorona is definitely not a good representative, though its remake does redeem it a little. The series as a whole has gotten much better as time goes by.