Halo 4 should be loosely based of H3. But it needs to evolve. Sprint should've been in since Halo CE or 2. Loadouts? Is been 4 years since H3 and they're S4's, of course they're going to be better equipped.
1-50 rank system sucked so bad in H3 because you could easily boost with friends for a lot of the time. And even buy accounts. It proved little. People weren't expecting Halo 3, they were expecting Halo 4. If you want to play 3, go and play it instead. We don't need a remake with the title Halo4.