Of course adding more cards is a risk, but that does not mean you have to add six copies of each to pull it off. Unless you're making an anti FG deck, sure, you need the full combo against those ruthless AIs. But as for PvP and so forth, not everyone has permanent control, and that is what makes the combo more and more viable for usage. You don't need to overfill on Protect Artifacts, maybe only carry two in a deck. All in all, it would amount to about 2 PAs, 2/3 Gravity Shields, and 2/3 Diamond Shields and you're pretty much set for a casual battle. You don't need much Gravity Shields, you could even just have a Gravity Mark! When you don't even draw the right shields, you could probably just do double Diamond Shields as you will have many Earth Towers to spare for the job. For the rest of the deck space, that goes to your preference on how you play.
Edit: If you want to argue about my opinion on what I see as amazing or not, feel free to do so.
Arguing about how I like things is all fine and dandy.