Just remember the lighter (and softer) the filling, the more easily it will be squished out of the cake from the weight of the cake layers on top of it. I would suggest you use a filling that will firm well upon refrigeration, and use thinner layers of cake with thinner layers of filling in between them. cake, filling, chill (the filling until firm), cake, filling, chill, etc until you’ve reached the desired height of your finished cake.
Something else to think about, you may wish to use a cake that contains oil instead of butter (butter cakes are very firm when refrigerated - I don’t mind eating them cold, but some people do). Additionally, the frosting you choose will have to be taken into consideration too - I wouldn’t serve cold buttercream frosting, but maybe top your cake with more of the raspberry mousse and garnish with fresh raspberries (leaving the sides of the cake exposed so that you can see the cake and filling layers).
Just some thoughts.