Hi. You get to decide if what you read here is constructive or not, but please know it's all kindly meant. In your case, I'm taking you at your word that you're not getting the interest you hope for and treating that as a problem to solve. So, I'm going to tear your profile apart. Please don't take it personally, because it's about your profile, not you.
So, first, your photos are not inviting. The one of her curled up is lovely, but the are others are throwaways for various reasons. I'll explain if you like, but it's a little complicated and I'd rather not waste the words unless you're curious. Instead, please focus on photos of the two of you clothed, together, taken from far enough away that your blurred faces occupy less than a third of the photo. And, yes, because you're primarily searching for couples, a provocative shot of her is a nice teaser (it's mostly men doing the hunting), but not one that emphasizes her youth.
He is, as Velma pointed out, 47 and your toggles top out at 45. We like what we like, but you're indicating that he's two years past his pull date. If he's too old for her, then he's too old for me, regardless of my age. Since you already are trying to overcome the fairly significant dual deficit of a large age difference and her extreme youth (ask me how many 42 year old women are going to be supremely confident having their guys play with her), that's not going to go over well. At all.
Your tagline is fine, but the first letter is capitalized and it doesn't need that period.
I'll get to the specific sections shortly, but my initial impression is that the two of you are far from a sure thing in looking for compatible playmates. Like, maybe you will, but you probably won't. If that's not accurate, you might want to think about how you position yourself generally.
Looking For is really meant to be about the people you're looking for - you have some of that, but it isn't particularly inviting - and a bit about what you're looking for. Is it FWBs? NSA? A social as well as sexual connection? There is a hint here, but not phrased in a way that anyone would read it and say, oh, hey, that sounds like what we want too. Do say something about who you're looking for, mention solo women if you are actually interested in them as well and perhaps flesh out what he might be looking for in solo play.
In Description, you've wasted words on things that are in your stats and photos - height and appearance - and added that thing about him looking significantly younger, which generally signals some sensitivity about age. You've also talked about yourselves as individuals rather than as a couple, which sends yet another less than optimal signal about your relationship. I'm certain it's unintentional and untrue, but that's kind of the undertone to this approach.
Instead, talk about the kind of couple you are and only a little about yourselves as individuals. Focus on who you are and what your interests might be.
I'm not sure what is going on in Fantasies, but what you've written contains nothing about your fantasies or real experience. If it was a little less like a shopping list, I'd say it goes in Looking For, but it's very much like a shopping list, so maybe consider leaving it as part of your private conversation that needn't be shared with others.
Additional comments is the second place where you seem to indicate you're not necessarily interested in swinging, although you'd like some of the social aspects. Maybe talk some more together if that's not what you mean to convey.
The Sydney University thing is based on an internet hoax. Please delete it in its entirety.
That's all I have for now. I hope you collect more opinions, makes some changes and then come back for a review.