Depends on the flavor of rough you're after (physically rough, humilatiing / insulting, always on or including aftercare, etc) as there's a pretty good spread of options to choose from. Light spoilers ahead.
Ardia feels more that she just starts taking you for granted, using you more like a favorite toy in time, but isn't all that 'rough' in my opinion so much as just emotionally neglectful. Not sure if her content is entirely finished yet. The writing does feel like it gets a bit more into subspace than most though. Good if you want the addiction / mild mind control sort of angle.
Sera is the abusive asshole domme both physically and verbally, though it's largely a facade she wears and you do get a rare peek behind the mask that lends her character some nice depth. She's also available from the start of the game and is one of the few rough dommes who will eventually give you a collar. If you like it extra spicy she may be the one to go after, though personally I like her better as a sassy tsundere sub (I'm a sucker for a good tsundere though). Includes pregnancy option.
I've not yet slogged through all the (annoying to me) cloak and dagger bits to actually reach akane and try her so can't say much there other than she's the most pain in the arse / involved to access and I'm hoping she'll be worth it. I will say she's also the only non-herm on this list, if that matters.
My personal favorite so far is Bimbo-Domme Seigwulf who goes in the physically demanding angle but follows up with a bit of emotional support / aftercare and a few soft scenes available and is the only domme you can take with you everywhere (complete with leashing if you get a collar from elsewhere). Includes eggnancy option.
https://wiki.smutosaur.us/TiTS/Siegwulfe
Mirrin offers something that I think more approaches a 'realistic' option in that she's a normal-ish person most of the time, but gets kinky physically dominant in bed, then takes good care of you afterwards. Pregnancy is largely mandatory to get to this domme's long term repeatable content I think.
https://wiki.smutosaur.us/TiTS/Mirrin
Zephyr is a possibility though her content is less developed then the others presented so far. I think you could view her as a lighter version of Sera, physically rough / demanding and a bit verbally dismissive but with a softer side that can come out if you have kids with her. Given her smaller amount of content though she feels more like a "quickie / fast food" domme good for a quick fix with not a lot of hoops to jump through or strings attached.
https://wiki.smutosaur.us/TiTS/Zephyr
I should add this list may not be exhaustive but I think this covers most of the more fleshed out rougher dommes with a good bit of content available.