I've always liked decks that have a fairly straightforward strategy like Speedrill; attack for lots of damage with few energies and keep doing so until all prizes are taken. Recently, the deck has required a little more strategy due to thinks like Mr. Mime and Dusknoir SF/DP, but the basics are still there.
My deck previous to this one was Scizor/Cherrim, which was basically the same thing, only with more tanking involved.
My future deck will hopefully be Seviper LL, as long as it's a PT-on format. Considering RR-on, I would make Vespiquen/Combee from Revived Legends (Vespiquen on bench with a damage counter, Combee out front attacking for 80 + poison).