First off, I think that your club/ball combination is good.
With the price, usually spin and meter speed becomes better, as does the distance. The latter is double edged because it spoiles the distance charts.
Spin effects depend on the clubs used with the balls. Therefore, I suggest to have balls and clubs fit together - no use to waste credits on top balls with low level clubs. My personal rule of thumb is, "ball level should not be above club level". Thus and IMHO, for you only the Srixons or lvl 33 Callies will fit.
Edit: ... in addition to the SD /edit
I've been playing the SDs long time but I changed to these Callies eventually because they provide better spin while length and "feel" aren't too exaggerated, together with the price.