If you plan to play in tournaments later on, it might be wise to avoid upgrading any more nymphs. Tournaments often require cards that aren't upgraded, and the effects of upgrading a nymph aren't worth that trade-off. Sorry to have to tell you this after you already upgraded one... many players make this mistake early, as there isn't a big warning sign in-game that says "ARE YOU SURE YOU WANT TO UPGRADE THIS NYMPH?"
That said, I see a couple quick tweaks that would greatly improve this deck: first, remove the Quantum Pillars/Towers, as they do very little for your deck. Second, if you're running Entropy quanta only, the un-upgraded Dissipation Shield is actually better at blocking damage than the upped Dissipation Field - it gets a 3:1 absorption rate instead of a 1:1 rate. Make the switch and you'll see a HUGE difference.