While it isn't the best for competitive multiplayer, Halo: Reach is a very solid entry into the Halo franchise.
Halo Reach is a surprising return to form for Bungie and the Halo franchise. Bungie knew it would be their last entry and it shows. The campaign is the best since the original Halo and the set pieces are impressive. Many slight improvements were made that I enjoyed in particular, such as giving the Elites and Grunts their alien languages back. I felt that this makes them much more menacing and alien in their presentation. The game is polished to a high level both graphically and aesthetically. The game just looks really good. As for the gameplay itself, I'll divide that between campaign and multiplayer.
The campaign was surprisingly good, save for a few weak segments. You know the ending from the beginning, but it's very well executed. A constant theme of the game is sacrifice, and one sees this play out among their squadmates and the planet as a whole. Fighting the Covenant across the planet is immensely satisfying and the game has a bit of a Combat Evolved feel to it. Most players will miss the Battle Rifle, but for me the DMR is just as serviceable. The reticule bloom is a bit of an annoyance at times, but it's not overly crippling. In truth the new Needle Rifle is a better all around weapon. The vehicle segments leave something to be desired, especially the space battle. It seemed unnecessary and shoe horned in. Probably because it was unnecessary and shoe horned in. Overall the campaign is quite good however.
Everyone seems to play these games for the multiplayer though, so let's look at that. Competitively speaking, this game is a step down from Halo 3. The reticule bloom adds an element of randomness that rewards spamming as often as it punishes it. Couple that with the much maligned armor lock and jetpack and you have yourself a pretty broken multiplayer from a competitive standpoint. Later playlists would fix a lot of these issues, but those playlists are always less populated. If you aren't a competitive sort, there's plenty of fun to be had here. All the beloved playlists make a return. Snipers, SWAT, and even Zombies are all as fun as ever. The new maps aren't the best though. The best maps in the game are remakes of the Halo 2 maps. Countdown is among the worst the franchise has to offer, along with The Cage.
All in all, Halo: Reach is a very satisfying addition to the Halo franchise and a fine last entry for Bungie. It's not without its flaws or infuriating moments like every Halo has, but it's good enough to be one of my favorites in the series.