Had been in the same situation, starting with the Special edition and then added Apassionata 1.
I was undecided for a few weeks between extending to Apassionata or Solo Strings. In the end I took the Apassionata extended. It gives you some nice trillers and effects, that can come handy for movie or game compositions, where Efx are needed.
The SE extended will also give you more instruments, but for me it was unattractive, because many of the new instruments consist of Brass and woodwinds, which I don´t need that much.
Have a look at the sample content table and compare.
Apassionata 2 gives you the muted articulations. If you are low on budget, I´d recommend to go for another library first.
The Elements library is always worth a look. I like it, because you get results, that never sound artificial, whereas with many other orchestral instruments you have to really go deep into programming and articulation theory to make it sound like a live orchestra.
An impulse like percussion sound on the other hand is very impressive and realistic out of the box.