Tim Stevens at ConsoleDomain has reviewed Halo, giving it a full 5 out of 5 rating, calling it a must-have game. There wasn't anything about the game he didn't like, but he focused more on gameplay balance, AI, and other elements, not just graphics:

One of the most impressive aspects of Halo is the intelligence of your enemies and comrades. Even though John is like a one-man army, you are only truly alone in the game about half of the time. The rest of the time you join up with friendly troops that are scattered about Halo to help with current objectives. They help you hold swarms of Covenant troops at bay; sweep corridors when you're trying to keep someone alive and chat to each other and you while youТre going about your business. They tell you whether someone's behind you, if another wave of troops is incoming, if someone dropped a grenade and even say Nice shot! when you show off your sniper prowess. These aren't mindless drones, they're surprisingly good at what they do, and having a few friendly AI snipers sitting on the ridge behind you as you charge into the thick of things can help things considerably.

Even so, Stevens calls Halo the best looking FPS in existence.