If you can get it to work, that will be an awesome terrarium!
I agree with JLAP, unless you find a way to provide some ventillation, the greenhouse effect will likely roast your plants!
Drilling holes into the lid without cracking/scratching it would be difficult.....perhaps you can instead make some acrylic/plexiglass cubes and put one at each corner of the pyramid to elevate it above its base so as to create a vent along the entire base.
This would decrease temps....but also humidity. It would also necessitate more frequent watering.
Whatever you decide to do, maybe you could introduce what you consider to be the "hardiest" of the plants you want to grow, and see how it does for the first 1mo. If it can't survive, then at least you'll know without sacrificing many plants.