In my opinion the Vector class is severely lacking, as others have mentioned. At the moment it may as well be a Point2 for the usefulness it provides. Vectors are an intrinsic part of 2D and 3D graphics and the argument that a newbie may be scared by a few extra member functions is extremely flawed. If a newbie is scared by vectors, no graphics library will ever hope to help them create things. As mentioned there is no great maths needed to be implemented, the entire additions could be restricted to
* Normalize ( Change to unit length )
* Dot product
* Cross product
* Norm (or length)
These things are not difficult to implement, nor are they difficult to understand, I myself have already added these functions my copy of DSFML in order to make use of the library. If this does not suit, the possibility of migrating this to a maths section of SFML, or even implementing an external mathematics library to handle the whole solution.
Things like n-dimensional vectors are largely useless with graphics related tasks, so I don't see why they're mentioned, however matrices are also useful, and this could also be added. At the moment I see the take on maths to be too newbie oriented, focusing on simplifying things they are going to have to learn anyway, rather than catering for more advanced users also.