I also have a raspberry cider going right now in a primary, but with only 5 ciders under my belt I'm still pretty new at this too and therefore will stick mostly to what I've read.
According to your SG readings this is going to be one strong cider/ on the verge of wine! If the hydrometer readings are changing the cider is still fermenting (you gave your yeast a lot of sugar so not too surprising), even if at a slow rate. Be patient. I'd just continue to let it go all the way till it is done fermenting and settled (not rack, stir, shake or add yeast nutrient...unless it smells like sulfur). If you wanted to add more raspberry flavor you could do this later via extract or racking and then adding more raspberries/raspberry juice for a couple months before bottling and aging.
What type of cider are you going for? Dry? Semi-sweet? Sparkling? I'm going for a dry sparkling raspberry cider. So I'm gonna let it get all the way down to about 1.000 or .990 (wherever it becomes stable), rack into secondary for a couple weeks (mine has raspberry pulp and seeds still in it so there is a lot that needs to be cleared out...don't know how clear yours is or if you have the same issue because you used raspberry juice...if clear then shouldn't need to rack at all) and then prime and bottle. Although the raspberry addition is not out of the question if it doesn't have a strong enough taste.
If you wanted a sparkling semi-dry one then you could look at Pappers_ Easy Stove-Top Pasteurizing thread (it's stickied so should be pretty easy to find). Haven't read every page of that thread though so don't know if you could do it with such a high abv?
Could also sweeten if you wanted to by allowing it to fully ferment then back sweeten with a non-fermentable sugar (xylitol, splenda, etc.). People definitely have their opinions about the taste these guys add so read up on them if this is the route you want (do you like the taste splenda adds to soda?).
