I don't know a whole lot about the Vertex in a chart, but from what I have read it would seem that when a person's points or planets conjunct the other person's vertex, then they are important to the Vertex person.
In this case, you and your boyfriend have your Ascendants conjunct each others' vertex's. That's about all that I can say about that, but hopefully there is someone else on here can follow up with more info.
His mercury conjuncts your descendant. This shows that he would be willing to move in together or that he at least thinks of you in terms of domestic bliss. His sun also inhabits your 6th house. This creates an imbalance in the relationship as this is a house of servitude. He will gear his life and actions towards supporting you and your endeavors. This sounds wonderful (and is) for you. You'll just need to watch out that his needs are not completely swamped and ignored (by him especially) or he could become resentful down the line. Your sun conjunct your MC, shows that this is a very real danger as your focus is definitely on where you are going. That said, your sun inhabits HIS 4th house of hearth and home so we can see why you are interested in co-habitating with him.
His Mercury, Pluto and Venus occupy your 7th house showing there is an abundance of attraction and even a willingness to work together. You have no planets in his 7th house but your Mars rules it. We find that your Mars is in his 4th house and conjunct Ceres. Ceres is an asteroid that has to do with nurturing
http://www.bobmarksastrologer.com/Ceres21.1.html. You can draw your own conclusions from this as I don't study asteroids all that much. My knee jerk thought is that you feel compelled to really take care of this guy (4th house Ceres conjuncted by your Mars).
Still, after looking at all of this, I can't pronounce that this seems like a good idea. The relationship between personal planets is missing and what seems to really be coming through via the synastry is that this is a relationship of conveinence and interdependence more so than real love. I think after a while it will probably stop working as neither of you will get what you ultimately want.
When I look at your composite, I feel that it shows the truth of the relationship itself quite well.
The sun is in the 11th which shows wonderful friendship and a willingness to work for the common good of all and to do so together, but it doesn't point towards work within the relationship itself. That's not the focus. The moon is in the 3rd house which is a pretty weak placement, especially since it's all by itself and making no contact to personal planets. You guys get along well enough and communication is pleasant enough, but that's about it.
A NN exactly conjunct the ASC seals the deal for me. This relationship is superficial. There is not a lot to it other than what you do for each other and others. With the NN in the 1st, then we know the SN is in the 7th. It looks like you've already done this one.
I've uploaded the composite so that you can have a look at what I see. Also, please keep in mind that I use whole signs instead of placidus, so maybe there's someone else out there that uses your preferred house system. Still, while this relationship may not kill you with extreme violence, rage, pain, etc, it might kill your spark for life. Too much duty and responsibility, not nearly enough love and enjoyment.
