As the moderator of this board, I'm a little disappointed to read that you (a long-time lurker) would fear being insulted by others here. I feel that the posters on this board have made every effort to try to make this "a safe haven" for any kinky questions newbies might have and everyone has remained quite civil.
In any event, you might misperceive the BDSM community. Quite a few of us are single, myself included. We might want a kinky life partner, but have trouble finding one. Others are coupled, but perhaps one partner doesn't enjoy kink, so that leaves the kinky one to try to look for it elsewhere outside the bedroom. Usually, that is best accomplished with an agreement between the couple, rather than a husband sneaking out on his wife. And polyamorous relationships are also quite common in our community. It's not necessarily about us not being able to get off with just vanilla sex. It's just that kinky sex rocks our worlds a whole lot more when we can play that way. Think of it like extreme sports, but extreme sex instead.
Professional Dommes are what is known as "Service Tops". They will play ANY WAY THAT YOU WANT TO PLAY, because YOU are the one with the fantasy that they are trying to fulfill. The only exception to that is if you are requesting something that is not on "the menu" (like sex, if the Domme doesn't offer sex). Many Dommes do have intimidating, bassass, "extreme" looking photos on their websites because they are trying to appeal to submissives/bottoms who want to be challenged. If they posted photos of them looking sweet and kind, they wouldn't get as much business. Rest assured, most of these goddesses are sweet and kind when they aren't "in character". I know from personal experience.
If you want sensual domination, it might not be the type of scene that they would do in their private lives, but they will gladly accommodate your request. ESPECIALLY if you tell them that you are a first-timer and want to take it slow. Yes, in many cases, they will be toning down their true sadism, but they know that's part of the job. (Like Burger King used to say, "Have It YOUR Way.") If you connect with one; however, you might find yourself being able to accept more pain with your pleasure as the trust grows between you over multiple sessions and you being to want to explore your own limits.
Now, as for "offering up the kind of experience" you want, your note was kind of cryptic. What is your base understanding of BDSM? Have you tried anything yet? If so, what did you enjoy? What did you dislike? What have you seen and want to try?
I'm working under the assumption that you are looking for a submissive/bottom experience. If that's not the case, then my advice will change . . . Maybe take an hour to write down your kinky fantasy. That can be invaluable when it comes time to negotiate what you want your session to include (especially if you are on a limited budget), and you can even present that to your BDSM provider in advance so that She can get a feeling for what you want.
I'm personally not a big fan of escorts playing dominatrixes, because they often lack the needed safety training and can potentially do serious physical, emotional or psychological damage without realizing it, but the reality is that most dominatrixes won't offer sex, so if that's part of your fantasy, you'll need to be more selective. The good news is that some of them do, and they even post on this board.