Support Jirachi is a great partner for Roopushin. It's 4x resistant to Psychic and resists the odd flying move as well. Jirachi can help Roopushin a ton by using Light Screen, Wish and Doom Desire. I can't tell you how much Roopushin loves Light Screen and Wish can get Roopushin back to full since you had to switch. Finally, Doom Desire is very strong now and makes the opponent have to choose carefully what pokemon has to take the hit and it ultimately gives you more turns to boost.
As for the Subpunch set, I'd highly consider Iron Fist. Substitute will be protecting you from status already and Iron Fist boosts Focus Punch to 180 before STAB! That's just sick.
I don't support the 252 HP/252 At spread because you simply are too weak to special attacks and it really hurts your survivability. I could justify it on a Sub or TR set, but not for Bulk Up.
As for the Subpunch set, I'd highly consider Iron Fist. Substitute will be protecting you from status already and Iron Fist boosts Focus Punch to 180 before STAB! That's just sick.
I don't support the 252 HP/252 At spread because you simply are too weak to special attacks and it really hurts your survivability. I could justify it on a Sub or TR set, but not for Bulk Up.