--My two cents - That album is great and just having a beautiful presentation is half of the challenge. As for your panna cotta with caramel fudge cubes...could it work? Yes. Will it work? Depends.
There are two different situations I run into all of the time at work. Sometimes I get several weeks notice that I will need to present new desserts. This allows me time to be very creative, do research and tweak the recipes multiple times to get the right textures and flavors. Other times something comes up last minute, I have a VIP vegan guest or something. In those situations I find from experience it is best to stick to components I already know work well. I can change the flavors slightly or combine new things, but I tend to stick to what I know will work without much tweaking needed.
That said, my only concern with your description is the fudge caramel cubes. How firm are they? Will they be too chewy next to a delicate panna cotta? Do you have a recipe that will hold its shape well? If not, you may want to go with something simpler: a layered chocolate and vanilla panna cotta with caramel sauce. Or a cardamom panna cotta with a honey dried fruit compote, etc..
What i have done in the past, get a half gastro tray/ (medium sized, shallow rectangle) spray it good with the oil spray. make your pannacotta and set it in that. Cut into 10cmx4cm portions and voila, pannacotta without dariole moulds.
Note: Add a few more gelatine sheets, works better if more stable.
Hope this helps