Breakaway vs Starscream Sideswipe vs a random named new decepticon Jolt vs a random named new decepticon This would give Jolt and Sideswipe more screentime then in ROTF.
Some locations I'd like would be the Grand Canyon, Earth's outer atmosphere (maybe go as far as the Moon and Mars), and Cybertron. As for hand-to-claw brawls: Soundwave vs. Jolt, Ironhide and Ratchet. Prowl vs. Barricade. Primus vs. Unicron. Optimus vs. Megatron (duh). The Dinobots and Omega Supreme vs. Starscream's Seekers.
Prime vs Megatron (obviously) Ironhide vs Barricade Jolt vs Decepticon Sideswipe vs Decepticon Soundwave vs Ironhide, Ratchet Starscream vs Prowl Unicron vs Captain Lennox