main attacker? 50 damage for 3 energies is waaaaaaaaaaaaaay little
Yeah, I know. It sucks. I've had to Uxie Lv.X+Palkia Lv.X combo to take the basics out, as Roserade does so little damage. I even end up charging Bronzong sometimes.
While I would like to have a big hitter here, the problem is that most big hitters aren't suitable here. Either they need Rare candy (Not much point when the rest of the deck doesn't), don't gain free retreat from Moonlight or are just too setup-intensive.
If you dropped 2-2 Bronzong you would be able to get 1-1 Azelf and 1-1 Mesprit in, but with 4 psychic energies, you won't be Supreme Blasting for long. The Bronzong lineup can also be dropped for 2-2 Swalot, which does a good 80, but only if your opponent has less HP. If Swalot had 100, this would be doable (as 130 HP - 30 snipe - 10 poison = 90 left), but without it, it would be another 90 HP pokémon to swarm the bench with. Somehow Deoxys doesn't cut it either, as it needs load of energy, and you won't be able to utilize the Normal Forme, which usually is the most effective of them all, with the deck that removes your opponent's energies.
But the point of this deck is that even little damage stacks. If it takes 3 turns for Kingdra to retreat a Claydol just to get to throw an attack for 80 (60+20), then the 3 turns you hit for 30 with Roserade will put your average damage above Kingdra's. Unless of course you're playing against healing decks, but those decks aren't usually hard-hitters (Tangrowth, Torterra DP) and have some heavy retreat costs which are easily Palkia-exploitable (Sceptile, Claydol). Butterfree could cause problems here, if it didn't play Claydol...
If there were an easy-to-tech-in Basic/Stage 1 hard hitter with low energy costs with free retreat from Moonlight, it could easily replace the Bronzong line. Now that there isn't... well, the deck is still doing pretty well.