Cuppy, first let me say that I don't know about using gelatin as a stabilizer in a cream cheese frosting or the weather in your country. It's hot and humid here in the south and what I do is make a stiff shortening based buttercream and add a little cream cheese to lightly flavor it but not enough to soften the frosting. Hope this helps..
Butter/cream cheese/powdered sugar frosting never holds it's shape for me without being sickly sweet. What I've found works is mostly shortening with a little butter and a little cream cheese (for the flavor) with powdered sugar, almond and vanilla extracts. Beat with a paddle at medium/low speed for a long time and it becomes fluffy without air bubbles.